AudioCircle

Industry Circles => NuPrime Audio => Topic started by: John Casler on 25 May 2016, 11:06 pm

Title: MCH-K38 - a giant killer!
Post by: John Casler on 25 May 2016, 11:06 pm
The BEST AMP I have EVER heard (at ANY price) has 8 channels!


OK, I have been holding off on writing this for a while to continue to log time on this amp.

I have also wanted to get feedback from my customers who have it and have listened to it SERIOUSLY.

I have been a dyed in the wool AudioPhile since about 1972, when I purchased and Stacked Mirror Imaged Dalhquist DQ-10 speakers.

I have heard hundreds of absolutley INCREDIBLE Stereo and Monobloc amplifiers in hundreds of systems and rooms.

Marantz, Citation, Pass Labs, SAE, Spectron, Phase Linear, Crown, Cary, Classe, MBL, Atma-Sphere, BAT, Hegel, Bryston, Carver, Ampzilla, NuFORCE, CineNova, ATI, Lexicon, Nakamichi, NAD, CinePro, Boulder, Eagle, Levinson, Audio Research, Krell, and on, and on.

I have heard amps that cost over more than some peoples homes at the time.

Now much of my impressions would clearly be shaped by the System and Room I have heard these amps in, but when an amp is GOOD, and in a GOOD systems, and you know what to listen for, you should be able to get an idea of what is high quality sound, and what is just good.

Most of these amps were either Stereo, or Monobloc Pairs.  They mostly (the good ones) were expensive, and all had reputations for performance and often a pedigreed Designer (like Bongiorno, Iverson, Pass, Carver, Levinson, etc) who were legends in the world of amplifiers.

So I am prefacing this with all that information, so you don't get the idea I am not to familiar with High Performance Amps and High Performance LISTENING to them.

That is why it is all the more STARTLING for me to make the CLAIM that is coming.  In fact, I still hesitate to post such a CLAIM since it sounds somewhat IMPLAUSIBLE, even to me.  But HERE GOES:

The Best AMP I have EVER HEARD (EVER) in my or any system, is the NuPRIME MCH K-38 eight channel amp, with the channels I am using BRIDGED to 400wpc.

No, it is not some $40,000 Stereo, or $25,000 Monobloc, but an 8 channel with BRIDEGABLE channels.

And the most STAGGERING thing about it, is that it it only costs $3000!!!!

This is difficult for my mind to wrap around, but the assessment is NOT JUST MINE.

Most recently I have heard the AMPZILLA 2000 (300wpc $8500 pr) Monoblocs, the BRYSTON 4bSST, ($5000)  and 7bSST ($11,000) monoblocs, the NuFORCE Reference 18 ($7600 pr originally), and the Pass Labs, and Atma-Spheres. Only a couple come close to matching the K-38 in a few categories.

Not one of these amps, nor any heard previously totally matched or exceeded the MCH K38 in ANY sonic performance category, and the K-38 smoked some of the VERY BIG BOYS quite badly in most.

To tag this amp a GIANT KILLER is a serious UNDERSTATEMENT.

Now I post this because many are looking for a Serious Amp, but they don't have 5 digit checkbooks.   I also know that virtually NO ONE, including me, would be looking at an 8 channel amp, and only using 4 channels bridged to 400wpc for their SERIOUS LISTENING SYSTEMS.  Well, all I can say is "go ahead" and spend $5000-$50,000 and get the same or lower performance.

I have a feeling that even NuPRIME does not fully appreciate the qualities and performance available from this amp. 

You know how I know?  THE PRICE!!!!  From what I have heard (and I admittedly haven't heard every amp out there) there is NOTHING that can compare at even 4-10 TIMES the price.

So THAT is why we are demoing the MCH K-38 at THE HOME ENTERTAINMENT SHOW next week in our 2 channel rig.

I plan on OPENING SOME EARS and hope you can stop in and hear for yourself, before Rustydoglim comes to his senses, and doubles or triples the price on this incredible amplifier.

I'll post more later, including some quotes from recent customers.

And if you already own the K-38 congratulations and if you haven't already, get your serious listening cap on and see EXACTLY WHAT I AM TALKING ABOUT.



(http://www.nuprimeaudio.com/media/rokgallery/4/4c52df73-1496-407f-aa11-46d7086816d0/5d1b444c-cab6-46a7-8d19-b0f2b16ac44b.png)
(http://www.nuprimeaudio.com/media/rokgallery/c/c8971d00-cbd2-4dd3-9c8a-ac511786d434/02fc2f7d-87f0-4452-8ecb-2fc612a91ec2.png)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Rocket_Ronny on 25 May 2016, 11:14 pm
Very interesting read. But there is no way it will give the 3D, holographic, imaging a good tube amp will. I am talking about the lit up from within, individual images being 3D and not flat like most solid state amps, except Class As. Is this an A/B amp?
Anyway I hope you are right as it gives a new option for top shelf sound. BI, or Tri amping anyone?

Rocket Ronny
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 25 May 2016, 11:29 pm
Very interesting read. But there is no way it will give the 3D, holographic, imaging a good tube amp will. I am talking about the lit up from within, individual images being 3D and not flat like most solid state amps, except Class As. Is this an A/B amp?
Anyway I hope you are right as it gives a new option for top shelf sound. BI, or Tri amping anyone?

Rocket Ronny


Hey Rocket - I would have agreed with you 100% until I heard it. I'm a huge fan of triode class A tube amps. Yes they are insanely wonderful. However - the damping factor has always been an issue - especially in the bass region.


Some time ago, David Hafler created the equivalent of a tube circuit for his Transnova amps. Turned out to be pretty awesome. So here we are today...


That said, enter Class D. Once considered dirty words, it has turned out to be very interesting. The NuPrime is a Class A/D amp. (Class A circuit design with Class D back end efficiency.) In fact, it does sound like a refined tube amp but with no issues on damping in the bass region. I have had some Audio Research gear and currently one of my amps is a hybrid Class A front end (tubes) and a transistor back end biased to Class A. The NuPrime makes that amp sound like a $250 receiver - well not that bad.


I hope you can hear the NuPrime - it's really worth some time and will challenge your thinking on amps. I can say this - at first glance I passed on it. After hearing it - I bought one.


Happy Listening,
Mark
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 25 May 2016, 11:36 pm
Very interesting read. But there is no way it will give the 3D, holographic, imaging a good tube amp will. I am talking about the lit up from within, individual images being 3D and not flat like most solid state amps, except Class As. Is this an A/B amp?
Anyway I hope you are right as it gives a new option for top shelf sound. BI, or Tri amping anyone?

Rocket Ronny

Hi Ronny,

Strangely enough the most noticable qualities when I first started listening were:

1) Imaging Palpability
2) Improved Depth of Images
3) An uncanny Transparency hearing detail either somewhat hidden, or never heard before
4) Larger Soundstage
5) Bass Dynamics and Harmonic Overtones.

While there certainly can be disagreement on what qualities are most important and how they rank in importance, this amp far exceeds what I thought possible at this price point.

It is also beyond interesting that BRIDGING the channels actually makes them sound BETTER.

And you are correct, if you have Bi-AMPABLE Speakers you have your amp.



To read more CLICK HERE (http://www.nuprimeaudio.com/index.php/products/amplifiers-and-preamps/multi-channel-amps/mch-k38.html)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 25 May 2016, 11:44 pm
Oh, and Ronny here is the info on the classes:

<<<<<The MCH-K38 amplifier is derived from the ULCAM (Ultra Linear Class A Module)+Class D design first introduced in IDA-8.  By joining a powerful high impedance single-ended amplifier circuit in the preamp stage with a well integrated Class-D power stage, the MCH-K38’s rich tube-like sound and tremendous speed is sure to impress audio enthusiasts.>>>>>

So part of the sound quality is the inclusion of even order harmonics, resulting in a more tube like quality, without giving in to the some of the tube downsides, as Mr EVOKE, just mentioned.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mca on 25 May 2016, 11:45 pm
Make a two channel version and you would get my attention!
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Folsom on 25 May 2016, 11:51 pm
Honestly I don't think your associated gear isn't good enough to make this claim true for everyone.

Do you know if your DAC has a buffered output? It uses an Alps Blue Velvet (not that good). 

Sounds more like you've achieved synergy.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Rocket_Ronny on 26 May 2016, 12:04 am
Cool, just read up on them. Class A front end for the 3D imaging and power of Class D. I like it. Are the ST-9, 10, and integrated up to the same sonic performance?

If I did not already own some Tube Research Lab gear I would considering a purchase.

Rocket Ronny
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 26 May 2016, 12:07 am
Cool, just read up on them. Class A front end for the 3D imaging and power of Class D. I like it. Are the ST-9, 10, and integrated up to the same sonic performance?

If I did not already own some Tube Research Lab gear I would considering a purchase.

Rocket Ronny


Hey, Rocket - I heard the smaller integrated. It was truly amazing. Then I hear the smaller STA amp. Same clarity - but the "weight" and authority were astounding.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Rocket_Ronny on 26 May 2016, 12:12 am
Nice.

I see a nuforce 20 amp on the site. Is Nuprime a division of Nuforce?

Rocket Ronny
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 12:23 am
Honestly I don't think your associated gear isn't good enough to make this claim true for everyone.

Do you know if your DAC has a buffered output? It uses an Alps Blue Velvet (not that good). 

Sounds more like you've achieved synergy.

Hi Folsom,

My Associated Gear not good enough? Not sure what that means, but obviously any and ALL amps will be facilitated and or possibly degraded by associated gear.  I cannot make ANY claim as to what you will hear, except based on what I hear.

I also have no idea what ALPS volume control you are talking about in my gear.

I think the DAC-10H I use, has the MUSE 72320 or similar. 

I would agree that the system has acheived a high level of synergy, and that translates to the overall product.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: OzarkTom on 26 May 2016, 12:26 am
Make a two channel version and you would get my attention!

+1
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 12:32 am
Nice.

I see a nuforce 20 amp on the site. Is Nuprime a division of Nuforce?

Rocket Ronny

Ronny,

No, NuPRIME is a NEW separate company, but has some of the original NuFORCE staff.  Optoma bought NuFORCE some time ago and NuPRIME took responsibility for the current REFERENCE Gear, of which the REF 20 was part of.

That marketing agreement has since ended, and the REF 20 will now be sold under the NuPRIME Logo/Name.

I do not include the REF 20 in my comparisons (as it should perform even better) because I have not personally heard it.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 12:42 am
Cool, just read up on them. Class A front end for the 3D imaging and power of Class D. I like it. Are the ST-9, 10, and integrated up to the same sonic performance?

If I did not already own some Tube Research Lab gear I would considering a purchase.

Rocket Ronny

There is always Audiogon  :green:

I will have a pair of STA-9s here in a couple days to compare.  I was under the initial impression that they were the same, except "4 in a box", bur Rustydoglim said there are differences, so I will report.

The ST-10 is in the same League, but with some slight sonic differences.  It is less tube-like, and has a slight leading edge transient attack that makes a special difference on "struck" instruments, like piano and percussion.  Overall just a slight bit more aggressive.

ST-10 also is rated at a conservative 150wpc, so it is less powerful than both the bridged K-38 400wpc, and bridged STA-9 290wpc.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 12:44 am
Make a two channel version and you would get my attention!

This IS a 2 channel version, with spare channels thrown in  :lol: :lol: :lol:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 12:54 am
 Here is a message I received and was granted permission to post, by a new K-38 owner

<<<<Hi John,

I got the amp yesterday and set it up with the HD AVP in my downstairs system.

AMP:  I can only say positive things about this amp, it’s a masterpiece

-Even running the power hungry VMPS RM 30’s full range, the power was effortless and vast
-I heard bass I never heard before, coming out of those speakers!
-Even without break in time, the amp is nuanced, smooth, yet detailed.  Yes, much smoother still than the V3 SE’s.
-Music had excellent bloom and dynamics
-The sound field is vast.  On two channel listening, there were sounds coming from center (such as voice of course) but the other instruments were held in space, sometimes way out to the left or right.  In one fun recording (Deep Forest), there are sounds that go behind you in the listening position.  Incredible imaging and depth.

Bridging was really easy and intuitive.  One little note: the manual says to use the white connector ends, but the red ones were active, not the white, when in mono mode.

I used 6 channels bridged for my front three channels and the remaining two for sides, unbridged.  Works great.>>>>
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 26 May 2016, 01:42 am
How much better than NuForce Reference 20?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 01:50 am
How much better than NuForce Reference 20?

I have not personally heard or auditioned the Ref 20 (as I mentioned above).

The K-38 is the equal to the REF 18 in most areas and IMO slightly better in tonal quality and detail than the Ref 18.

The K-38 bridged also has more "horsepower" than the REF 18, 400wpc compared to 335wpc.

That said, the REF 20 is a the flagship, and while it is hard to imagine, I assume it would be better, but my criteria was "The BEST AMP I EVER HEARD", and I haven't heard that one.

I might mention, that one of my GOLDEN EARED Clients has purchased TWO K-38's and is planning on bridging each to get 8 channels at 400wpc.

He will receive his second in about 10 days.  Maybe he will post (I know he reads AC)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 26 May 2016, 02:08 am
I have not personally heard or auditioned the Ref 20 (as I mentioned above).

I'm just asking ...anyone... who might know.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Folsom on 26 May 2016, 02:11 am
Audio Alchemy has basically a 2 channel version. It's class A front end, class D. Better? Probably, but wasn't the end all if you ask me.

A lot of equipment makes up for problems elsewhere in the chain. I don't believe it makes it correct however, or really good. But it can provide synergy.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: MttBsh on 26 May 2016, 02:34 am
How would the K-38 sound using only 2 of its 8 channels?

I have a Schitt Yggdrasil DAC feeding a Tortuga LDR preamp to a pair of Sophia Electric 91-01 single ended 8 watt mono tube amps to some high efficiency Cain & Cain speakers (and two subs). Would replacing the Sophia amps with the K-38 be power overkill in my system?

Any thoughts would be greatly appreciated!
Thanks
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: kevb on 26 May 2016, 02:59 am
Audio Alchemy has basically a 2 channel version. It's class A front end, class D. Better? Probably, but wasn't the end all if you ask me.

A lot of equipment makes up for problems elsewhere in the chain. I don't believe it makes it correct however, or really good. But it can provide synergy.

I have owned/heard a few digital amps in my time.  PS Audio, Hypex, Tripath, etc.  I have also had amps the likes of Plinius, Edge, Audio Research, Classe, Bryston, Simaudio, etc. The little IDA-8 integrated is at least the equal of any of those in almost any sonic parameter you wish to choose (beyond in a lot of cases save bass power) on any speaker I have in the house, and the STA-9 I have now is a step up from that providing more bass drive and power.  They simply do not sound the least bit digital, but nor do they sound like solid state.

Seems you know an awful lot about how these sound by reading sales brochures of other amps.  Why don't you try one before you condemn them with faint praise and brush them off?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Folsom on 26 May 2016, 03:09 am
Which sales brochure am I reading?

I haven't heard any classD, whatever front end, sound overly smooth, yet.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 26 May 2016, 03:22 am
 :
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Armaegis on 26 May 2016, 03:47 am
Too bad the amp couldn't run in a parallel-bridge config to utilize all 8 channels in a typical 2 channel system.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JackD on 26 May 2016, 04:06 am
Folsom

How appropriate do you think it really is for another "Industry Person" who is selling his own amps to be making comments in another manufacturer's Circle about products he knows nothing about or has by your own admission never heard? Maybe you need to keep your point of view to yourself about products you haven't seen much less heard. 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 26 May 2016, 04:13 am
+1
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: PMAT on 26 May 2016, 04:29 am
Very bold claims. If it's true, great. That is a horrible delivery of such a claim though.  :o 
Risky on the credibility level.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Folsom on 26 May 2016, 04:34 am
I didn't realize I was posting in an industry circle. I was just responding to what seemed like some intense hyperbole. And at no point have I said NuPrime makes a bad product. I simply don't believe in intensely biased things with so many variables. Also I doubt NuPrime believes their products wildly stomp on everything. They're very intelligently designed, but to meet goals of price points that aren't as high as new cars is integral.

Frankly I'd be happy to be on a friendship level with NuPrime designer/s, but the thread is taking a hostel attitude in the face of discussion so it may not happen at the moment.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JackD on 26 May 2016, 04:52 am
Folsom

What "hostile attitude" are you referring to?  If you mean me challenging you about jumping into an owners circle thread then that is not hostile, but just a matter of fact.  You are actively selling an amp based on "chip" technology from TI, but feel the need to challenge John about a product you have never seen or heard.  I own multiple pieces from the company and may find John's claims over the top, but if I challenge him it is as a product owner and not as a competing manufacturer.  That "Industry Participant" tag comes with constraints and is why it is there, so look, read and think before you jump in.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Folsom on 26 May 2016, 05:05 am
Define "Actively"... If you mean selling PCB's and providing endless support, sure.

Obviously I'm not here to be derogatory. I'm just a guy with some thoughts on a subject of one amp vs all others.

For the record the front end schematic for these amps appears above average for sure so it's no surprise that people are enjoying them. Low noise front, low noise classD. It's a hard combo to beat on the budget.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 05:06 am
How would the K-38 sound using only 2 of its 8 channels?

I have a Schitt Yggdrasil DAC feeding a Tortuga LDR preamp to a pair of Sophia Electric 91-01 single ended 8 watt mono tube amps to some high efficiency Cain & Cain speakers (and two subs). Would replacing the Sophia amps with the K-38 be power overkill in my system?

Any thoughts would be greatly appreciated!
Thanks

I would think the K-38, while overkill already, for your system it might be even more so.

Give me a chance to spend some time with the STA-9 and see how it compares.

The Sonic Qualities of the STA-9 are supposed to be even more "smooth, and tube like", which may be better suited to your speakers.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 05:36 am
Good to see a lot of "passion" regarding amps, which is EXACTLY why I posted my opinions.

But rest assured ANY EVALUATION of Audio Gear is OPINION, based on Subjective and or Objective assessments.

Anyone reading AudioCircle knows that there are HUNDREDS of criteria on which YOU judge your gear.  I am the same way, but have had the luxury of "maybe" hearing more samples over the years, as well as clearly knowing what I think makes good sound.

My purpose in posting this thread was to offer some information about what I, and a growing number of EARS have been hearing in the K-38

As well, this SOUND and SOUND QUALITY is coming from a highly unlikely, and therefore LESS VISIBLE component.  Who would ever think an 8 channel amp could rival MegaBuck 2 Channel or Monoblocs?  Most see an 8 channel amp and think, lower quality, and acceptable sound for Dolby ATMOS systems

NOT SO.

So, I am "shining a light" on the product, and it is worthy of that light.


Don't think I didn't know there would be skeptics, and doubters, and of course my post was based TOTALLY on my ears, experience, and preferences.  You have to know that YOUR experiences may be different.

That said of the 5-6 close owners of K-38 owners (including myself) who have been using their amps and had a chance to do a little, or a lot of critical listening, they ALL say pretty much the same thing.  The have NEVER Heard anything better.  In about a week, I know of 2 more who will be receiving their K-38s and hopefully they will drop by, and add to the conversation.

So is it Hyperbole to say that an 8 channel amp sounds as good, or better that any amp I have ever heard?

 NOT WHEN IT IS Exactly what it is.

YMMV, but if you get a chance to hear one, then you can decide.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 26 May 2016, 05:49 am
Hello, John.

I've heard the K-38, and it did sound fantastic. I cannot say it's the best I've ever heard for a couple reasons: my aural memory is pretty short, I heard it on totally new and unfamiliar speakers in a room (and what a room it is!) I had never been in before. Nonetheless, I am mightily impressed with the K-38.

John,

I'm looking forward to your pronouncement on the STA-9 amp. Hopefully, you'll have two in dual mono.

Michael
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eric Gustafsson on 26 May 2016, 06:11 am
I'm a happy owner of two STA-9 used as monoblocks and I'm very impressed of the sound.
For the money it's a giant killer.  :thumb:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: MttBsh on 26 May 2016, 06:36 am
I would think the K-38, while overkill already, for your system it might be even more so.

Give me a chance to spend some time with the STA-9 and see how it compares.

The Sonic Qualities of the STA-9 are supposed to be even more "smooth, and tube like", which may be better suited to your speakers.


Thanks for your response John, much appreciated! I look forward to your assessment of the STA-9.
Title: NuPrime STA-9 inside
Post by: maty on 26 May 2016, 06:54 am
@John

Is it possible for you to upload a photo of the K-38 inside?

Audiocircle NuPrime STA-9 inside (http://Nuprime STA-9 inside)

-> http://www.audionet.com.tw/a/thread-8356-1-1.html

(http://maty.galeon.com/WP-imagenes/hard/Nuprime-STA-9-inside.jpg) (http://maty.galeon.com/WP-imagenes/hard/Nuprime-STA-9-inside.jpg)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 26 May 2016, 07:17 am
Anyone reading AudioCircle knows that there are HUNDREDS of criteria on which YOU judge your gear.  I am the same way, but have had the luxury of "maybe" hearing more samples over the years, as well as clearly knowing what I think makes good sound.

John, don't take this too literal or personal. Audio gear and systems as a whole are sort of like... women... (up to a certain extent). The more time you spend with them, the more you get to know them. If the relationship (or relationships) are positive and enduring - not merely a brief encounters or even worse ...one nighters - you really get to know that piece of gear ...or woman. She (or it) makes a memorable and enduring impression.

But if you're a gear slut so to speak in the sense that you always have a lot of girls on the go, you'll never be in a position to rightly judge the intimate knowledge that only comes from having an enduring relationship.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 26 May 2016, 07:18 am
Deleted- I hate using the iPad for this.  :evil:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rajacat on 26 May 2016, 08:43 am
Very bold claims. If it's true, great. That is a horrible delivery of such a claim though.  :o 
Risky on the credibility level.
+1
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: alexreusch on 26 May 2016, 02:39 pm

(http://www.audiocircle.com/image.php?id=143658)


I can just agree 100% on all the positive posts, reviews and comments about the MCH-K38. I am using the multichannel combo HD-AVP/MCH-K38 and I am totally happy about the sound experience. I also run my front channels in balanced bridged configuration (6 channels) and the remaining two channels (rear left/right) unbalanced not bridged.

(http://www.audiocircle.com/image.php?id=143660)



The sound stage is really amazing!  :thumb:

For pure audio listening, I use the high quality USB DAC (the HD-AVP has two separate DACs) in a stereo configuration (only front left/right channels are powered on). BTW: The USB DAC of the HD-AVP is equal to the DAC-10H. A very nice solution for feeding my USB DAC with high quality content is the Sonore microRendu in combination with roon (the microRendu is a supported roon endpoint). What can I say more? It is probably the best audio solution available on the market for a very reasonable budget. Ahh.. as background information: My speakers in use are the Piega Coax 70 (front) Coax 10 (rear) and Coax Center.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 26 May 2016, 03:29 pm
@alexreusch

Two questions:

1ª Do you live in Reus / Tarragona / Spain? I live in Tarragona.

2ª Do you use a power conditioner?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: alexreusch on 26 May 2016, 03:34 pm
@alexreusch

Two questions:

1ª Do you live in Reus / Tarragona / Spain? I live in Tarragona.
No, I do live in Zurich, Switzerland

2ª Do you use a power conditioner?
Yes, I use the Isotek EVO3 Aquarius, the unit at the bottom in my rack.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 26 May 2016, 03:45 pm
Bad luck for me (I would have invited me to your house)  8)

Usually, traditional Class D amplifiers are connected directly to the wall. It is very good to know that NuPrime Class A+D amps tolerate a power conditioner!!!!
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 26 May 2016, 05:15 pm
John, don't take this too literal or personal. Audio gear and systems as a whole are sort of like... women... (up to a certain extent). The more time you spend with them, the more you get to know them. If the relationship (or relationships) are positive and enduring - not merely a brief encounters or even worse ...one nighters - you really get to know that piece of gear ...or woman. She (or it) makes a memorable and enduring impression.

But if you're a gear slut so to speak in the sense that you always have a lot of girls on the go, you'll never be in a position to rightly judge the intimate knowledge that only comes from having an enduring relationship.

Hi Windchaser,

And I do take what you said literally and personally and TOTALLY Agree.

Now of course, I have not had hundreds of MegaBuck amps in "long term relationships", (which would be difficult) but due to the level I have been involved in the Hobby, and the Business, I have a very large group of evaluating criteria that I have used (and refined) for decades.

As well, I have a significant number of specific and critically selected reference recordings that I have accumulated that provide comparative insight into reproductive abilities (that is speakers, not ladies  :nono:)

And of course, one can not truly evaluate gear differences without having it in the same system and room.

But, we can only do with the experiences we have had.  My evaluations are not and should not threaten or question the evaluations of others, and were not intended as such.

The sole purpose was to convey, 1) My utter surprise at the mind boggling sonic properties of this specific amp, which I have spent considerable time with now. 2) To provide a path to others, who might never have considered such an amp due to the fact that is seems "purposed" for an entirely different use.

Will it be THE BEST AMP "you" ever heard?  Only you can judge that, but up to this point, I have helped place a good number of these, and EVERY OWNER is very pleased.  I might think that some of them will find, like that fantasy woman you speak of, that the more time they spend in her Sonic Arms, the more IN LOVE they will be.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rajacat on 26 May 2016, 06:53 pm
DAC (Digital Amplifier Company) has also claimed to have built the best amp ever so you're not alone at issuing this opinion. What rubs me the wrong way is the hyped salesmanship. Since this is an "audiophile" forum don't you think that the over caffeinated sales pitch is overkill in addressing a relatively sophisticated audience? Hard sell sorta turns me off.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Brad on 26 May 2016, 07:35 pm
DAC (Digital Amplifier Company) has also claimed to have built the best amp ever so you're not alone at issuing this opinion. What rubs me the wrong way is the hyped salesmanship. Since this is an "audiophile" forum don't you think that the over caffeinated sales pitch is overkill in addressing a relatively sophisticated audience? Hard sell sorta turns me off.

Have you MET John?  :o
That's just his personality, and this is kind of subdued for him.
I heard it as him saying, "hey, here's something you might not have considered that has proven to be fantastic in my system"
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: OzarkTom on 26 May 2016, 07:36 pm
DAC (Digital Amplifier Company) has also claimed to have built the best amp ever so you're not alone at issuing this opinion. What rubs me the wrong way is the hyped salesmanship. Since this is an "audiophile" forum don't you think that the over caffeinated sales pitch is overkill in addressing a relatively sophisticated audience? Hard sell sorta turns me off.

And what about the Nores four years ago. I have noticed many of those fanboys have sold them, even the NC1200's.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: timind on 26 May 2016, 07:59 pm
And what about the Nores four years ago. I have noticed many of those fanboys have sold them, even the NC1200's.
That's exactly what I was wondering about as I read along through the thread.
 And for the record, I own a couple of NuForce pieces (neither are class D amps) and love them both.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mr_bill on 26 May 2016, 08:02 pm
I TRUST JOHN C and his opinions.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: kevb on 26 May 2016, 08:21 pm
All my previous digital amps I could not wait to sell because none of them could shed the artifice.  I have a pair of Crowns now, which were the best of the bunch, and I never truly warmed to those either - they are OK for the high power application that I need.  They all sound like amps, and digital ones at that.  Not the Nuprime's.  And I am a hard one to satisfy.  If it didn't perform up to the level of the oversell, they would be gone.  I was a skeptic who bought, and became a believer.   They tend to get out of the way of the music, which is a lot harder said than done.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: bummrush on 26 May 2016, 08:42 pm
Same here. It was almost like they made my skin crawl. But really one problem i had with was the bass, maybe it was my speakers, i dont know,it just seemed like there was way way to much,to overpowering. It was all i focused on.I know some can like that,but its not for me one bit. It certainly wasnt what you'd hear in a performance.  Is this at all similar to anyone else?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 26 May 2016, 09:02 pm
Same here. It was almost like they made my skin crawl. But really one problem i had with was the bass, maybe it was my speakers, i dont know,it just seemed like there was way way to much,to overpowering. It was all i focused on.I know some can like that,but its not for me one bit. It certainly wasnt what you'd hear in a performance.  Is this at all similar to anyone else?


I was VERY biased against Class D in every way - no pun intended. I was a total Class A or tube guy. However, Class D has really matured in so many ways. I wouldn't have believed it until I heard it - but the NuPrime blew me away. That's my experience and I bought their amp. I've owned Audio Research, a behemoth Yamaha M-2 (remember those), Transnova Hafler, Bryston and a VTL for a while until my friend demanded them back.


There are still pro class D amps that I really dislike. They're mostly for brute power on concert tours etc... I don't think it's fair to compare those to audiophile companies that are really trying to develop this technology.  Oh - as a side note - I don't have to run the air conditioner when my amp is on anymore  :lol: :lol: :lol:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: kevb on 26 May 2016, 09:37 pm
Same here. It was almost like they made my skin crawl. But really one problem i had with was the bass, maybe it was my speakers, i dont know,it just seemed like there was way way to much,to overpowering. It was all i focused on.I know some can like that,but its not for me one bit. It certainly wasnt what you'd hear in a performance.  Is this at all similar to anyone else?

My Crown XLS-2500's were like that with my Usher CP-6311's.  At least until the volume was goosed a little.  Then the balance seemed to be restored.  But you are correct about the skin crawling thing - I find that most non-tube amps make me suffer from than feeling....with the notable exception of the NuPrime(s). They make me feel more relaxed during listening sessions.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 26 May 2016, 09:47 pm
Traditional class D amps have problems with the tweeter or HF, creating an artificial sound.

With a class A buffer the sound is better. And with the addition of even harmonics (via pair of JFET), like new NuPrime amps, a hopeful future opens for class D, I think.

The ideal is an integrated like Nuprime IDA-8 but with good/last dual ESS Sabre DAC, bigger toroid and capacitors. And we can adjust the power of the harmonics is the future too.

Title: My NuPrime Gear Just Arrived !!!
Post by: Evoke on 27 May 2016, 02:47 am
OK - my HD-AVP and MCH-K38 just arrived. They are not hooked up yet. But as a marketing guy / audiophile / etc ... I can tell you that the products are packaged as nicely as an iPhone. Very cool.  So the first thing you see after unpacking the components is a RED label about selecting voltage. Don't see those too often.

Onto something interesting. I used to have a Lexicon pre-amp. The manual was like a book. Brilliantly written. A pain in the you know what - but you could always find the answers. Well, the NuPrime stuff has an iPhone like short printed manual. If totally iPhone like - there would be a gazillion page manual online.

I really want to play with this stuff... I plan to bridge 4 channels for 400 x 2 for my mains, and that leaves 200 x 4 which I will use 3 channels for my center and surrounds. This gear is VERY involved and after the last few glasses of Chardonnay, I think I will wait until tomorrow before I start hooking things up. :thumb:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: G Georgopoulos on 27 May 2016, 03:18 am
Traditional class D amps have problems with the tweeter or HF, creating an artificial sound.

With a class A buffer the sound is better. And with the addition of even harmonics (via pair of JFET), like new NuPrime amps, a hopeful future opens for class D, I think.

The ideal is an integrated like Nuprime IDA-8 but with good/last dual ESS Sabre DAC, bigger toroid and capacitors. And we can adjust the power of the harmonics is the future too.

Hi Maty

you mention class-d with 90% efficiency,and you say class-a buffer sounds bettter with 25% efficiency,i wont go to hf problems with class-d (could be ultrasonic beating with audio freq. creating distortion and noise in hf),then you say ida-8 is ideal but with ess sabre dac?,then bigger toroid and caps with class-d?my view is these are smaller than other amps (smps),but if it is conventional ps?would they be bigger?yes! you're right!

the reason i respond to you is i'm really confused...

please explain, is your opinion objective or subjective?

thank you and regards
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 27 May 2016, 06:47 am
I would have to write about other amplifiers using class D and how they have improved the sound but this is not the thread.

A good class D integrated, with DAC, only have ONE buffer -> S/N is better than two or more buffers.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 27 May 2016, 06:53 am
Have you MET John?  :o
That's just his personality, and this is kind of subdued for him.
I heard it as him saying, "hey, here's something you might not have considered that has proven to be fantastic in my system"

Thanks Brad,

Yes, that is it.

Strangely enough, I toned my "actual" enthusiasm DOWN a couple notches before I hit post.  :lol:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 27 May 2016, 06:57 am
I TRUST JOHN C and his opinions.

Thanks Bill.

Those who know me, know I take this seriously.

I wanted to write and post this thread almost 2 months ago after I first heard the amp, as I was FLOORED.

But, I felt more comfortable exploring it in greater detail, and having multiple listening partners listen to see if THEY would hear the same things.

They DID :thumb:
Title: Re: The Best Amp I have ever heard (at any price) has 8 channels!
Post by: srb on 27 May 2016, 09:08 am
Strangely enough, I toned my "actual" enthusiasm DOWN a couple notches before I hit post.

Excessive use of bold and CAPS can actually UNDERMINE credibility and turn a post into an over-the-top CARTOON.

Using LARGE FONTS further reduces the chance of being taken SERIOUSLY.

My $0.02 ..... I think it's best to let carefully chosen words convey the message, then italics, underline or bold can be sparingly applied when needed for a little emphasis.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Rocket_Ronny on 27 May 2016, 12:03 pm
I don't mind the CAPS and Enthusiasm, or salesmanship. John is a dealer after all. Adds to the entertainment value.

Rocket Ronny
Title: Re: The Best Amp I have ever heard (at any price) has 8 channels!
Post by: wushuliu on 27 May 2016, 12:32 pm
Excessive use of bold and CAPS can actually UNDERMINE credibility and turn a post into an over-the-top CARTOON.

Using LARGE FONTS further reduces the chance of being taken SERIOUSLY.

My $0.02 ..... I think it's best to let carefully chosen words convey the message, then italics, underline or bold can be sparingly applied when needed for a little emphasis.

Yeah i thought it was some kind of joke at first.
Title: Re: The Best Amp I have ever heard (at any price) has 8 channels!
Post by: Wind Chaser on 27 May 2016, 03:01 pm
Like  Elaine Benes and her penchant for exclamation marks, John has a long standing history of using bold text in his posts when he wants to make a point; that's just his style.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jtwrace on 27 May 2016, 05:10 pm
And what about the Nores four years ago. I have noticed many of those fanboys have sold them, even the NC1200's.
If you're going to throw stones it might be best to know the reason(s) before doing so.  While it might be funny while sitting behind your computer wherever you live there are humans on the other side. 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: OzarkTom on 27 May 2016, 05:35 pm
If you're going to throw stones it might be best to know the reason(s) before doing so.  While it might be funny while sitting behind your computer wherever you live there are humans on the other side.

 :scratch:

So why did you and so many others sell their Ncores, the worlds greatest amps. You tell me.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: zybar on 27 May 2016, 05:44 pm
:scratch:

So why did you and so many others sell their Ncores, the worlds greatest amps. You tell me.

I sold my Ncore 400's and bought NC 1200's.

They aren't the world's greatest amps and other than one poster who shall remain nameless, nobody ever said they were.

What there were AND still are, are outstanding amps that sound fantastic and can drive almost any speaker.

BTW, I sold my NC 400's in about 24 hrs...so clearly there is still a demand for them years later.

Lastly...Is it really necessary to put down product "x" to talk positively about product "y"? 

Just enjoy your purchase and talk about its positive aspects.

George
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rajacat on 27 May 2016, 05:50 pm
If someone sells the product, you can be sure that their review of the product is not objective.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 27 May 2016, 06:07 pm
ALL reviews are subjective.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: zybar on 27 May 2016, 06:09 pm
If someone sells the product, you can be sure that their review of the product is not objective.

All reviews are subjective and all contain our own experiences, prejudices, etc...

I have dealt with John before and he is a good guy who stands behind the products he sells.

While I don't subscribe to his over the top approach, that's just who he is and the perspective buyers will figure that out quite quickly.

George
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Rocket_Ronny on 27 May 2016, 06:15 pm
Quote
If someone sells the product, you can be sure that their review of the product is not objective

You cant assume that. It all depends on the person and their honesty. Just because money is involved does not mean EVERYONE is dishonest. That was FUN, using all caps and such.

ROCKET RONNY
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rajacat on 27 May 2016, 06:18 pm
ALL reviews are subjective.
Of course all reviews are subjective but its also true that your own self interest can color your perceptions regardless if you realize it or not.
Actually, I think this is more a debate over styles of salesmanship. It's that I prefer a more low key approach that respects the intelligence of the prospective buyer.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 27 May 2016, 06:46 pm
I think this is more a debate over styles of salesmanship. It's that I prefer a more low key approach that respects the intelligence of the prospective buyer.

You're right on both accounts. The less a salesman says, the better. OTOH I don't have a problem with a salesman calling attention to something someone else has said.

In spite of John's style, I can still appreciate his enthusiasm and respect his experience. We can all learn a lot from each other and that's what keeps me coming back.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 27 May 2016, 06:58 pm
You're right on both accounts. The less a salesman says, the better. OTOH I don't have a problem with a salesman calling attention to something someone else has said.

In spite of John's style, I can still appreciate his enthusiasm and respect his experience. We can all learn a lot from each other and that's what keeps me coming back.

Thanks Windchaser, and while this has gone off track, the more important thing is that someone looking for an INCREDIBLE sounding Amp, at a reasonable price, MIGHT just consider a HIGHLY UNLIKELY Candidate.

And glad you appreciate my enthusiasm, as it has been a long time since I have been so impressed with a couple products, and THAT is why I have them (or will) in my system and offer them to others with similar goals.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rajacat on 27 May 2016, 07:05 pm
You're right on both accounts. The less a salesman says, the better. OTOH I don't have a problem with a salesman calling attention to something someone else has said.

In spite of John's style, I can still appreciate his enthusiasm and respect his experience. We can all learn a lot from each other and that's what keeps me coming back.
Agreed! :thumb:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Hugh on 27 May 2016, 07:34 pm
You're right on both accounts. The less a salesman says, the better. OTOH I don't have a problem with a salesman calling attention to something someone else has said.

In spite of John's style, I can still appreciate his enthusiasm and respect his experience. We can all learn a lot from each other and that's what keeps me coming back.

Well said.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Hugh on 27 May 2016, 07:35 pm
Thanks Windchaser, and while this has gone off track, the more important thing is that someone looking for an INCREDIBLE sounding Amp, at a reasonable price, MIGHT just consider a HIGHLY UNLIKELY Candidate.

And glad you appreciate my enthusiasm, as it has been a long time since I have been so impressed with a couple products, and THAT is why I have them (or will) in my system and offer them to others with similar goals.

John,

I may need to stop by your place for a listen.  :)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 27 May 2016, 07:58 pm
Unimportant, so I deleted my post. Perhaps, others may follow my lead??
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 27 May 2016, 08:23 pm
If you're going to throw stones it might be best to know the reason(s) before doing so.  While it might be funny while sitting behind your computer wherever you live there are humans on the other side.

Coming from the guy who is constantly putting others down with insulting one liners..... Now I've seen it all.

Sorry John for being off subject.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: OzarkTom on 27 May 2016, 08:53 pm
I sold my Ncore 400's and bought NC 1200's.

They aren't the world's greatest amps and other than one poster who shall remain nameless, nobody ever said they were.

What there were AND still are, are outstanding amps that sound fantastic and can drive almost any speaker.

BTW, I sold my NC 400's in about 24 hrs...so clearly there is still a demand for them years later.

Lastly...Is it really necessary to put down product "x" to talk positively about product "y"? 

Just enjoy your purchase and talk about its positive aspects.

George





Hey George, what product y did I mention here on this thread?

There were a lot more than just one poster here that would jump anyone that said they did not like the Ncores, have you forgotten? No matter what the product is, if you search hard enough, you will find a negative on it on the net here. Is that the fault of the designer or the person''s system? Every designer likes to think their design is the best. Why build it, if not?
 
And on the Ncore tour, there were several listeners that did not like the sound of the over-hyped Ncores.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: wushuliu on 27 May 2016, 09:07 pm
So what kind of class d chip does this amp use?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 27 May 2016, 09:18 pm
And glad you appreciate my enthusiasm...

I would also like to be equally honest and confess that if I had the option of viewing anything anyone posted without unnecessary font deviations, I would make that my default setting.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 27 May 2016, 09:19 pm
So what kind of class d chip does this amp use?

It is a proprietary design. 

From the website:

"The MCH-K38 amplifier is derived from the ULCAM (Ultra Linear Class A Module)+Class D design first introduced in IDA-8.  By joining a powerful high impedance single-ended amplifier circuit in the preamp stage with a well integrated Class-D power stage, the MCH-K38’s rich tube-like sound and tremendous speed is sure to impress audio enthusiasts.  By utilizing a 1000W power supply and CMA capacitor array, the MCH-K38 fully exploits the Class A+D design’s ability to deliver massive amounts of power and speed when needed by a single or multi channels."

If that is helpful.
Title: Oops
Post by: Evoke on 27 May 2016, 10:09 pm
Posted in wrong thread
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: DARTH AUDIO on 27 May 2016, 11:11 pm
It is a proprietary design. 

From the website:

"The MCH-K38 amplifier is derived from the ULCAM (Ultra Linear Class A Module)+Class D design first introduced in IDA-8.  By joining a powerful high impedance single-ended amplifier circuit in the preamp stage with a well integrated Class-D power stage, the MCH-K38’s rich tube-like sound and tremendous speed is sure to impress audio enthusiasts.  By utilizing a 1000W power supply and CMA capacitor array, the MCH-K38 fully exploits the Class A+D design’s ability to deliver massive amounts of power and speed when needed by a single or multi channels."

If that is helpful.



Sounds like what Davialet is trying to pull off. Class A with Class D. I hope the NuPrime sounds better than the Devialet!! That amp had zero emotion! Like sitting in a room with all white walls!
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Armaegis on 28 May 2016, 06:50 am
And on the Ncore tour, there were several listeners that did not like the sound of the over-hyped Ncores.

Though what you're describing isn't really any different from virtually every new product that comes out. Announcement, hype machine, squawking parrots, units circulate, lovey dovey, more hype, a few detractors, anger disbelief, hype counterhype, more squawking, hype dies down, those who like it still like it, those who refused the hype feel vindicated, no one cares anymore except for the squawkers, announcement for next shiny thing comes out. Repeat ad nauseam.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 28 May 2016, 07:33 am

Sounds like what Davialet is trying to pull off. Class A with Class D. I hope the NuPrime sounds better than the Devialet!! That amp had zero emotion! Like sitting in a room with all white walls!

The key are the even harmonics. If we could adjust their level depending on the type of music and the format (I listen more very good 24/96 vinyl rips mastered analogically with tubes -> even harmonics; played with my cheap/second hand/tweaked AV Marantz SR4500 and they sound very well now after I having solved my serious problems with DC and RFI/EMI) we would have a winning product.

When the mastered is digital (after 198*) the sound is other, good sound but without emotion and even less if the phono used in the ripping is also digital.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 28 May 2016, 08:29 am
Though what you're describing isn't really any different from virtually every new product that comes out. Announcement, hype machine, squawking parrots, units circulate, lovey dovey, more hype, a few detractors, anger disbelief, hype counterhype, more squawking, hype dies down, those who like it still like it, those who refused the hype feel vindicated, no one cares anymore except for the squawkers, announcement for next shiny thing comes out. Repeat ad nauseam.

Very to the point, I've seen this happen so many times, I have fallen into the trap myself once. Most everyone wants to have the latest and greatest, it they are the competitive type and like to switch up gear on a regular bases. The senario you discribed is right on the money.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: timind on 28 May 2016, 12:03 pm
Though what you're describing isn't really any different from virtually every new product that comes out. Announcement, hype machine, squawking parrots, units circulate, lovey dovey, more hype, a few detractors, anger disbelief, hype counterhype, more squawking, hype dies down, those who like it still like it, those who refused the hype feel vindicated, no one cares anymore except for the squawkers, announcement for next shiny thing comes out. Repeat ad nauseam.

Kinda, but the hype for the Ncore was at a level I'd not seen before...or since. It was mostly confined to A/C if I recall though.
We're in the middle of one thread so far; we'll see what happens here.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: bummrush on 28 May 2016, 12:56 pm
It was the same when class d popped up years ago.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 28 May 2016, 04:43 pm
John,

I may need to stop by your place for a listen.  :)

Hugh,

Yes, I hope to see you at the SHOW.

We are in 1046
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: flat4 on 28 May 2016, 08:02 pm
John, i look forward to your input on the STA-9 also.  Nuprime gonna be at capitol audio fest?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 28 May 2016, 08:46 pm
Wow, I was busy for a few days and this thread just ran away.  As the co-founder of NuForce and now CEO of NuPrime, let me say a few things to summarise what is going on.

In 2005, The Absolute Sound, for the first time (of any audiophile magazines), gave the NuForce Reference 9 Product of The Year award. In that article, Chris Martens made a controversial statement that Class-D has arrived. Well, it took the next ten years and countless iterations of designs to finally master it. There aren't many companies engaging in high power, high-end class D design, most of them purchase the module from Ice Power or Hypex and tweak it from there.  And sure, those amp modules improved over time.
With every new models of UcD (now Ncore) or ICE, people raved about it. Likewise, NuForce plowed along with its own V1,2,3 series of amps.

A very layman explanation about Class-D concept: input analog signal is modulated into a series of pulses (think of your FM or AM signal). Unlike FM and AM, class-D uses the width of a pulse to represent the amplitude of the input analog signal that is sampled. So, you ended up with a series of pulses with the same amplitude but different width. The pulses are further manipulated to become pulses with bigger amplitude. And eventually the big pulses are then demodulate to become analog signal again to drive your speaker.  Other than converting the initial analog signal into pulses, there is nothing digital about this type of implementation. It is very analog in nature (ah, you have many ways to shape the sound using analog techniques). There is another type of Class D implementation that is very digital where input signal is converted into 1s and 0s using DSP to manipulate (Devialet and many low power class-D chips). The advantage of going digital is that you can do a lot of processing to change the sound (increase the bass, change the EQ, combined with DAC, etc).  So this is where Class D is often confused with all-digital amp. The drawback of this all digital approach is that it sounded "digital".

In the early days of Class-D "analog" implementation, engineers have not figured out how to improve switching frequency (of the pulses) and manipulate them, so people can detect various weaknesses (bass, HF extension, jitter, whatever). Solid state and tube implementations have weakness too. But engineers have worked on those designs for much longer period of time. Some people think that Class D is not high resolution and so it will always sound digital. Unless you are listening to live music, as long as music has to be recorded, along the way, resolution is "constrained", even with vinyl. 

By now, a handful of engineers who specialised in Class-D designs can implement switching frequency at more than 500kHz (CD is 44.1kHz) and in our lab, we have designs running at 1MHz, 0.0x% THD at wide range of freq and power, low jitter, etc.  Without going into details that get many people lost (and I can't explain anyway),  our engineers can now produce class-D amp that is near perfect.
This is not to say that most class-D engineers know how to do that. There are many bad class D implementations on the market too.

Unlike Ice Power or Hypex, we are not in the business of making high volume amp modules at low cost.  So we spend a lot of our effort in making different sounding amps.  See http://www.nuprimeaudio.com/index.php/reviews/amp-comparison.html (http://www.nuprimeaudio.com/index.php/reviews/amp-comparison.html)
Just like one of you who stated, high-end audio is like women (or men if you are one of those rare lady audiophile), not everyone share the same taste.  I would say that MCH-K38 is like a very sexy blonde that most men like. Make sense?

Lets talk about amp characteristic. There is no perfect sounding amp. And some characteristics are contradictory to others. For example, to make an amp "Warmth" sounding, it must have more even order harmonics. And it won't be as neutral and clear as one without even harmonics. A recording engineer might use both types of amps. A super clean and detailed amp as a reference, and another amp to help shape the sound. Electric guitar amp is intentionally made to have a unique sound, but it is used to produce the sound, not for reproduction.

Ref 20 was the NuForce top end reference amp, and it was designed to be as smooth, clean, detailed, dynamic, etc as possible. At NuPrime, we made a huge leap forward in not only how to build a world class amp, but many different sounding amps. Going from making one "near perfect" design to making many "near perfect" designs is a huge step. Very often, you improve something and you lose something else. So we want a tube amp to sound like tube, but I don't want to lose the dynamic and speed. Is MCH-K38 better than Ref 20, no, otherwise we would not have kept Ref 20 with NuPrime logo. but if you watch a lot of movies and also listened to a wide variety of music, you might actually prefer MCH-K38 over Ref 20. If you are into big classical music, you will likely go for Ref 20 or ST-10. If vocal is your thing, you will likely pick MCH-K38 or STA-9.

I think MCH-K38 strikes the right balance that impressed John so much. Yes, MCH-K38 is really something.
We won't be bringing out a stereo/mono amp using the same K38 amp. To do that would mean our R&D has stopped working on amp.

Oh, I want to talk about pricing. We don't price something based on how good it sounds within our own family or versus the competition. We are an engineering company.  We are not in the business of pricing our amps based on weight or extensive workmanship. We price our amps based on our cost. With more knowledge over time, the cost comes down while complexity and performance go up. I will use an example that most of you understand. You all know that switch resistors is an expensive high end preamp design. But we learned how to implement it using FPGA (it is a big logic chip) so this design that used to be in $5000 preamp, is now in every one of our integrated amp and DAC. We are talking about an order of magnitude in cost reduction (from a bank of expensive resistors to a chip). Similarly, our amplifiers use a naturally occurring self oscillating design principle to generate the PWM pulses for Class D sampling (instead of very expensive external PWM generator).  As we learned how to increase the frequency to 1MHz, instead of selling you a $100,000 amp, we might be able to sell you a $649 amp that priced like the STA-9. To be very honest, some other parts of the amp now cost more than the amp module itself. Power supply is now the dominant cost.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Hugh on 28 May 2016, 09:31 pm
Hugh,

Yes, I hope to see you at the SHOW.

We are in 1046

John,

I'll try to get away from our room.

When you get a chance, come down to Trabuco C in the lobby.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 28 May 2016, 09:39 pm
John, i look forward to your input on the STA-9 also.  Nuprime gonna be at capitol audio fest?

I just hooked up my first pair this morning and they are burning on an ISOMIKE test tone, burn-in track for LARGER systems.

I did a quick initial listen and was impressed with the out of the box performance.

Also spend a little time with the ST-10.

All three (STA-9, ST-10, and K-38) sound fantastic, but slightly different from each other.

It will take me quite some time to clearly define those differences via A/B listening, but they seem much like rustydoglim has posted in the AMP Chart.

It will likely be after THE SHOW unless someone purchases the show sample.



Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 28 May 2016, 09:42 pm
John,

I'll try to get away from our room.

When you get a chance, come down to Trabuco C in the lobby.

Got it.

I also want to hear your new Seraphin, and you need to hear our room partner EVOKE Loudspeakers.  They are my exact sound.  They have the VMPS (Cheney) and INFINITY (Nudell) Gene Set.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Armaegis on 28 May 2016, 10:26 pm
Kinda, but the hype for the Ncore was at a level I'd not seen before...or since. It was mostly confined to A/C if I recall though.

It didn't seem quite so bad to me, though I come from the headphone world which has a younger and more easily agitated crowd.

My view on the Ncores is not so much hype derailment, but moreso a failure on the manufacturer to really capitalize on it. First of all, their pricing structure kicked it off the tracks before it even really began. At 3x the price of the equivalent wattage UcD module, that's a tough pill to swallow. Secondly, there seemed to be hardly any community engagement/involvement afterwards, which is anathema to a DIY product. Even on their webpage, there is practically zero news. There has been no followups. No announcements on who their partners are that are using similar modules. Maybe Bruno is active on other forums, I don't know.

There was a great interest/hype generated right at the beginning, and with just a little bit of effort (hire a PR guy for goodness sake) could have kept it running, but instead they let it wither on the vine.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: wushuliu on 28 May 2016, 10:33 pm
It didn't seem quite so bad to me

Mmmm... it definitely had a vocal following. Reminded me of the NwWavGuy ODAC 'movement'.

I think Bruno is pretty active at diyaudio. But there are also so many diy amp modules out now that are inexpensive and sound excellent. A 1k+ diy amp is a real tough sell these days, with the possible exception of tubes.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: wushuliu on 28 May 2016, 10:34 pm
Power supply is now the dominant cost.

Ah. With Class-D, it often seems to boil down to the best power supply possible.

Thank you for the informative post!
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: timind on 29 May 2016, 02:27 am
It didn't seem quite so bad to me

Hah, I was moderating the circle which hosted the early Ncore threads. Great day for me when the Ncore circle was created. :D

As for the new NuPrime amps, I'll have to investigate them. The comments on the power supplies is encouraging as the SMPS is the main reason I had no interest in the Ncore.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 29 May 2016, 04:50 am
Rustydoglim,

Thank you very much for the informative post, I enjoyed reading your journey to where you are now and what you and your engineers have done to improve the product.

John, I look forward to hearing about your evaluation of the STA-9, both as monoblocks and as a single amp. I enjoy a warmer presentation and don't need the high wattage of the MCH-K38. My 97db speakers have servo subs so the amp will only be running the Mids and tweets with whatever amp I use.

Just for the record, I too don't really like large or bold text as it seems a bit over board in the sales department and is distracting to me. However, I'm happy that you get THAT exited about a product and I do realize by your posts that you really enjoy what you are doing.

Happy Memorial Day weekend everyone!

Greg
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Armaegis on 29 May 2016, 06:26 am
As for the new NuPrime amps, I'll have to investigate them. The comments on the power supplies is encouraging as the SMPS is the main reason I had no interest in the Ncore.
This was an interesting article by Benchmark (and if any company rides their reputation on numbers, it would be them) on why they switched over to SMPS in their gear: https://benchmarkmedia.com/blogs/application_notes/152143111-audio-myth-switching-power-supplies-are-noisy

What's never mentioned though is that while they've kept the switching noise out of the amp's output, what about anything that leaks back into the power mains? Cheap wall wart smps are notorious for putting garbage back into the mains.

I'd be curious to know what Nuprime's thoughts are on switching power supplies, as I believe they use both. The IDA-8 has a linear, the IDA-16 is switching, the STA 9 and 10 are linear, I think the K38 is switching??
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 29 May 2016, 11:36 am
Switching power supply (SMPS) and linear power supply each has its own advantages,and it also depends on the power requirement and sonic characteristics we want to achieve。I only stated the power supply has become a dominant COST,but the performance is still mainly dictate by the amp board.

AC->power supply->capacitors->amp board

So for smaller power requirement of a few hundred watts, we can use a large capacitors array to provide instantaneous power. Linear power is quieter but slower.  A high quality SMPS can be very quiet and extremely fast but it is expensive. MCH-K38 and Ref 20 need too much power so we used an expensive custom designed SMPS (very few company is capable for custom SMPS design). For STA-9 we want the warmth not only from the amp but also linear power.  IDA-16 is designed to be very clean and neutral,and need a lot of power in a small space,so custom SMPS was used.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 29 May 2016, 11:43 am
These are all fundamental engineering of power amp. If anyone try to explain in terms of some voodoo energy, alignment of something or or how atoms and electrons are manipulated they are in BS territory. There are some secondary effects that we can't correlate but the primary reason the amp sounded good is due to solid and grounded engineering.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: timind on 29 May 2016, 01:14 pm
Switching power supply (SMPS) and linear power supply each has its own advantages,and it also depends on the power requirement and sonic characteristics we want to achieve。I only stated the power supply has become a dominant COST,but the performance is still mainly dictate by the amp board.

AC->power supply->capacitors->amp board

So for smaller power requirement of a few hundred watts, we can use a large capacitors array to provide instantaneous power. Linear power is quieter but slower.  A high quality SMPS can be very quiet and extremely fast but it is expensive. MCH-K38 and Ref 20 need too much power so we used an expensive custom designed SMPS (very few company is capable for custom SMPS design). For STA-9 we want the warmth not only from the amp but also linear power.  IDA-16 is designed to be very clean and neutral,and need a lot of power in a small space,so custom SMPS was used.

This really makes me want to hear the STA-9. My objection to SMPS is based on reliability more than on sonics. 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 29 May 2016, 03:04 pm
A STA-9 with SMPS 500 or 600 will be a very good idea  :P

Maybe, Signal to Noise Ratio: < -95dB at 1W, 10W, 100W => with SMPS < -100 or 105 dB
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 29 May 2016, 03:14 pm
May 21, I proposed a dual mono with SMPS 500 in a class AB amp.

-> http://www.diyaudio.com/forums/solid-state/196089-l12-2-cfp-output-amp-120w-2-8r-28.html#post4721665
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Armaegis on 29 May 2016, 03:51 pm
Maty, you think swapping in a DIY power supply is going to sound better than what they designed???
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Wind Chaser on 29 May 2016, 04:06 pm
Anything built to a price point can be improved.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: maty on 29 May 2016, 04:25 pm
DIY or not, it depends on the specifications / measurements, with very little RFI/EMI like Hypex or Connexelectronic SMPS. Designed by NuPrime engineers would be ideal.

NuPrime STA-9 SMPS version with 500W or 600W => better S/N and more fast is a winner without doubt. To listen orquestal mass and not only vocal or commercial music. ALL type of music.

It will like a little MCH K38.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: bh46118 on 29 May 2016, 04:30 pm
It's John's job to promote NuPrime product, what's he supposed to do, tell you it sounds bad. My IDA-16 sounds every bit as good as he described.


Very bold claims. If it's true, great. That is a horrible delivery of such a claim though.  :o 
Risky on the credibility level.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 29 May 2016, 07:00 pm
These are all fundamental engineering of power amp. If anyone try to explain in terms of some voodoo energy, alignment of something or or how atoms and electrons are manipulated they are in BS territory. There are some secondary effects that we can't correlate but the primary reason the amp sounded good is due to solid and grounded engineering.

Thank you rustydoglim for an informative and no BS explanation of what you have accomplished and how. IMO, there is way too much hype and not enough good information about the products with other companies. And while I'm not a measurements guy per say, I certainly understand the importance of a good design. Listening and liking what I here is what really matters to me and I really appreciate your explanations of the type of sound each product produces.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 29 May 2016, 08:48 pm
It's John's job to promote NuPrime product, what's he supposed to do, tell you it sounds bad. My IDA-16 sounds every bit as good as he described.

Hi Bruce and thanks for your kind remarks.

I might add that I post this way in ALL my posts and emails when possible.  My Emails, FB posts, and forum posts are all written with various elements that emphasize my points.

I am not a lab coat listing specs, but an Audiophile posting thoughts and passion when I beleive it to be true.

My other, and main BUSINESS is in Health, Fitness, and Strength Conditioning, and if anyone thinks my AUDIO posts are over the top, hold onto your horses when I am on the Health, Fitness and Strength side.  :lol:

What is also really wild, is that I am now burning in the HD AVP (PrePro and Server) and I could easily start another thread that would ask "Could one of the best Preamps, actually be a Surround Sound PrePro?  And from what I am hearing early on, this may be the case.  :drool:

But, there are some clear caveats, personal preferences, and needs to consider.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 29 May 2016, 09:01 pm
Rustydoglim,


John, I look forward to hearing about your evaluation of the STA-9, both as monoblocks and as a single amp. I enjoy a warmer presentation and don't need the high wattage of the MCH-K38. My 97db speakers have servo subs so the amp will only be running the Mids and tweets with whatever amp I use.

Just for the record, I too don't really like large or bold text as it seems a bit over board in the sales department and is distracting to me. However, I'm happy that you get THAT exited about a product and I do realize by your posts that you really enjoy what you are doing.

Happy Memorial Day weekend everyone!

Greg

Hi Greg,

While I don't comment extensively on gear that I haven't had a lot of time with at this point, the AMP GRID that rustydoglim has put together seems to clearly give you an idea of the slight sonic differences.

My early "limited" listening of the STA-9 (bridged) seem to bear that out.  Even, only with a few hours on them, they tend to be a bit more "relaxed" than the K-38.  I have not had the opportunity to listen to the amp in Stereo Mode yet, and may not till after the show, next week.

I will post more when I get the time to do it justice.

And I hope you also have a GREAT Memorial Day.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 29 May 2016, 09:05 pm
John, i look forward to your input on the STA-9 also.  Nuprime gonna be at capitol audio fest?

See my response above.  I will report ASAP on the STA-9 in my system, but it will be after the show.

Rustydoglim will have to answer regarding Capitol Audio Fest.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Freo-1 on 29 May 2016, 09:19 pm
This really makes me want to hear the STA-9. My objection to SMPS is based on reliability more than on sonics.

Well, speaking of sonics, here is a link to switching power supplies from Benchmark:

https://benchmarkmedia.com/blogs/application_notes/152143111-audio-myth-switching-power-supplies-are-noisy?utm_source=Benchmark%27s+Application+Notes&utm_campaign=7445cef5f8-Application_Note_58_5_4_2016&utm_medium=email&utm_term=0_7c8c792ee5-7445cef5f8-34712529 (https://benchmarkmedia.com/blogs/application_notes/152143111-audio-myth-switching-power-supplies-are-noisy?utm_source=Benchmark%27s+Application+Notes&utm_campaign=7445cef5f8-Application_Note_58_5_4_2016&utm_medium=email&utm_term=0_7c8c792ee5-7445cef5f8-34712529)

The DAC-2 is easily the best sounding DAC I've heard to date.  So, they are onto something.

I have the Benchmark DAC-2 connected to Primare A32 preamp, and a pair of A34.2 power amps.  They all have switching power supplies, and the A34.2 amps are proprietary Class D, utilizing a Ultra Fast Power Device (UPFD) setup:

http://www.primare.net/default.asp?ContentID=33 (http://www.primare.net/default.asp?ContentID=33)

As a lifelong tube guy, I can state that the Primare setup with the benchmark sounds outstanding.  I've owned a LOT of gear over the years, including numerous high ticket items, and I'll put up the Benchmark/Primare combo against any setup.  While no system is perfect, this one gets pretty close to providing the illusion of a musical event happening.  Up until I heard this setup, would not have believed Class D and SMPS gear could sound this good (which includes Hypex and ICE products).

So, while not having heard the K-38, it would not surprise me in the least that this amp would sound great.  I'm now a believer that proprietary Class D amps can sound great.  would definitely like to hear one sometime.  The ability to bride it to 400 watts is a very nice feature.  The difference in performance with the Primare configured in mono at 550 watts is remarkable.  It's easy to understand why folks would want to get the higher power afforded by by bridging the K-38. 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 29 May 2016, 09:28 pm

As a lifelong tube guy, I can state that the Primare setup with the benchmark sounds outstanding.  I've owned a LOT of gear over the years, including numerous high ticket items, and I'll put up the Benchmark/Primare combo against any setup.  While no system is perfect, this one gets pretty close to providing the illusion of a musical event happening.  Up until I heard this setup, would not have believed Class D and SMPS gear could sound this good (which includes Hypex and ICE products).

So, while not having heard the K-38, it would not surprise me in the least that this amp would sound great.  I'm now a believer that proprietary Class D amps can sound great.  would definitely like to hear one sometime.  The ability to bride it to 400 watts is a very nice feature.  The difference in performance with the Primare configured in mono at 550 watts is remarkable.  It's easy to understand why folks would want to get the higher power afforded by by bridging the K-38.

Freo-1,

Thanks for your post, and i tend to agree that we are going to see (and hear) more of the MUSIC with technology like this.

If you are in Southern CA next weekend, we will be demonstrating this VERY Sound via some EVOKE Speakers that allow this to be appreciated.

If you're here, or close, stop by and say hello.  :wave:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 30 May 2016, 10:08 am
After consulting with the chief engineer, I have more details and very interesting information.

A class-D amp product is consisted of three main components:
Preamp Stage, Class D Stage, Power Supply
(note that this Preamp Stage is not the volume control preamp, but an integral front-end of the Class D amp design)

Preamp Stage design is made of
(A) Op Amp  or  discrete transistors and in NuPrime's designs there two types: (B)ULCAM (Ultra Linear Class A Module) and (C)SECAM (Single Ended Class A Module)
Practically all the amp products on the market use Op Amp for preamp stage. Only a few very high end products use discrete transistors design.  This is hard core analog design.  Tube or solid state amp is basically one BIG (giant size) transistor.  Now you can see why we could reproduce tube or solid state sound, while keeping the advantage of class D speed and dynamic.

Class D power stage design can be Half Bridge (H) or Full Bridge (F)

Power supply can be Switching (S) or Linear (L)

Now here's where things get really interesting.

IDA-16 =  A+H+S  (Op Amp + Half Bridge + Switching)  for clean, fast, and powerful
ST-10  =   A+F+L  for clean, fast, smooth and refined
IDA-8 =  B+H+L  for a little more warmth and fast
STA-9 = C+H+L  for tube-like sound, warmth, and fast
K-38 = C+B+H+S   

There are more combinations that we can do here:  C+H+S  or  C+B+F+L  or C+B+F+S
Chief engineer said there could be literally unlimited number of topologies using transistors for the preamp stage, but to get something good is very tedious work. 

I think NuPrime is the only company in the world that can offer this type of ultra high end custom design at budget price.
We plan to introduce Custom Audio (rack mount) very shortly for customers who order large number of channels (> 10) to do custom selection.  For example, you might want to have 10 channels of IDA-16 and STA-9 combo sound, but only need 50W per channel (multi-room high end back ground music).  We can mount the preamp stage of STA-9 with the Class D power stage of IDA-16, and one 500W SMPS. 

Or if you are a speaker company, we can custom design amp module for your active speaker.
Title: Little MCH K38 (stereo)
Post by: maty on 30 May 2016, 10:56 am
Will there be the possibility of a little MCH K38 with only two channels? Un/Balanced and bridgeable too like STA-9 (and the same price range).
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eisener Bart on 30 May 2016, 05:36 pm
After consulting with the chief engineer, I have more details and very interesting information.

A class-D amp product is consisted of three main components:
Preamp Stage, Class D Stage, Power Supply
(note that this Preamp Stage is not the volume control preamp, but an integral front-end of the Class D amp design)

Preamp Stage design is made of
(A) Op Amp  or  discrete transistors and in NuPrime's designs there two types: (B)ULCAM (Ultra Linear Class A Module) and (C)SECAM (Single Ended Class A Module)
Practically all the amp products on the market use Op Amp for preamp stage. Only a few very high end products use discrete transistors design.  This is hard core analog design.  Tube or solid state amp is basically one BIG (giant size) transistor.  Now you can see why we could reproduce tube or solid state sound, while keeping the advantage of class D speed and dynamic.

Class D power stage design can be Half Bridge (H) or Full Bridge (F)

Power supply can be Switching (S) or Linear (L)

Now here's where things get really interesting.

IDA-16 =  A+H+S  (Op Amp + Half Bridge + Switching)  for clean, fast, and powerful
ST-10  =   A+F+L  for clean, fast, smooth and refined
IDA-8 =  B+H+L  for a little more warmth and fast
STA-9 = C+H+L  for tube-like sound, warmth, and fast
K-38 = C+B+H+S   

There are more combinations that we can do here:  C+H+S  or  C+B+F+L  or C+B+F+S
Chief engineer said there could be literally unlimited number of topologies using transistors for the preamp stage, but to get something good is very tedious work. 

I think NuPrime is the only company in the world that can offer this type of ultra high end custom design at budget price.
We plan to introduce Custom Audio (rack mount) very shortly for customers who order large number of channels (> 10) to do custom selection.  For example, you might want to have 10 channels of IDA-16 and STA-9 combo sound, but only need 50W per channel (multi-room high end back ground music).  We can mount the preamp stage of STA-9 with the Class D power stage of IDA-16, and one 500W SMPS. 

Or if you are a speaker company, we can custom design amp module for your active speaker.

Which letters can be described P-20 and Ref 20?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: orientalexpress on 30 May 2016, 06:25 pm
Is there a 30 days try period?it's all about synergy with speakers.i hate to spend $3k and find out it's doesn't good or better then what i have.

lap
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 30 May 2016, 06:36 pm
P20 is not applicable in this discussion about power amp. Don't confuse the Preamp Stage of a power amp with a Preamp that does input selection and volume control.

Ref 20 is A+F+S
For a long time we have been using OpAmp just like everybody else. A high quality OpAmp circuit can be very good, as used also by many reference amps. But you can't tune the sound. So if you want to sound like tube, then you have to use transistors with tube characteristic. But unlike a tube what is one big transistor with all its good and flaws, we can do a lot with class D and transistors.
Ref 20 wasn't meant to sound like tube.
A Full Bridge class D power stage is more expensive but has an edge over Half Bridge design. So ST-10 and Ref 20 use Full Bridge design.
Switching Power Supply has to be used for so much power density.

I think what we are doing is really a revolutionary steps in Class D, not that the technique was not known by some of the most knowledgeable analog engineers. But it is the extensive mix of analog design techniques and class D designs that is ground breaking. You won't hear about magazines talking about this because nobody wants to promote budget amps with super high end designs.

With regards to a two channel K38, I stated that we have no plan, simply because K38 was designed to be the best amp for movies and music. Further more, the sound characteristic of K38 is quite "American". We have equally important customers in France (who have similar taste as the Chinese) that prefer STA-9, or Japanese and Germans who preferred neutral sound. So here lies the difficult of coming out with a STA-10. How do we strike the balance? So for the mean time, go buy K38 :)

Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: bh46118 on 31 May 2016, 08:22 am
Jason, I'm going to put you on the spot, :) for your personal listening which sound profile do you prefer ?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 31 May 2016, 11:45 am
Quote
Jason, I'm going to put you on the spot, :) for your personal listening which sound profile do you prefer ?
You will all be disappointed that I have very little time for music listening (well, I really need Omnia). When I am not traveling 50% of the time, at home I work long hours (I enjoy what I do, taking products to market and creating brands so it is not work to me). I am confined to my home office after 9pm and not allow to play music loud that disturb my family (heavy school work etc).

So, what I have at home is constrained by family and personal need, not necessary my dream system.  I am not into classical music or have room and time for large system. So I have the HD-AVA with the old NuForce S-9 speakers which is perfect for me. 
The HD-AVA amp is in between STA-9 and K38, sort of leaning slightly more toward music listening than movies.
I watch downloaded movies and TV programs so HD-AVA is perfect for me.  It is also connected to my home network by ethernet cable to access my Synology NAS where I kept everything there. So, one device that does everything for me.
I have WR-100 connected to HD-AVA for online streaming via Spotify.  HD-AVA already has AirPlay built-in for streaming.

On my desk, where I literally live 1/4 of my life, this is the setup  :thumb:
Facebook on iPad Pro, social media on iPhone 6+, computer in the middle, hidden behind the computer are NuPrime uDSD (for MacBook Pro) and Encore mDSD (for iPad Pro).  The Celsus Sound SP One speakers are great as monitor speakers but can also rock the room.
(http://www.audiocircle.com/image.php?id=143953)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Rocket_Ronny on 31 May 2016, 12:04 pm
Nice setup. I found at one time I did most of my listening in front of the computer as well. Now it seems it's in the truck. Did not stop me from adding a pair Rythmik FM8s to the main system. Have not hear them yet, but soon.  8)

Gave the speakers to my son and his professional video company, but you get the idea. He and his friends love the speakers and is their introduction to high end audio.
(http://www.audiocircle.com/image.php?id=40787)

In the end, it still is all about the music.


Rocket Ronny

P.S. How did you get your computer keys colored like that.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 31 May 2016, 12:29 pm
Quote
P.S. How did you get your computer keys coloured like that.
You can buy it at < $2 with free shipping from http://www.aliexpress.com (http://www.aliexpress.com)  (search for keyboard skin)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: MttBsh on 31 May 2016, 03:05 pm
Jason,
Thanks for the listing of sound characteristics of Nuprime's different amps, I really appreciate it. I like the sound you describe for the K38, but I currently have SET amps and high efficiency speakers so the K38 is probably too much power, so I am leaning towards the ST-10, which, from what I've read, strikes me as the K38 sound with the lower power I need.
My question: my preamp is a Tortuga LDR, which produces an extremely fast, clean, and refined sound - and then warmth is added in my mono tube amps. I prefer clean and fast over warmth, but do you think replacing my tube amps with the ST-10 would render the sound too lean in my set up? I know it's all a matter of personal preference but I am interested in your thoughts. Thank so much!
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eisener Bart on 31 May 2016, 07:49 pm
P20 is not applicable in this discussion about power amp. Don't confuse the Preamp Stage of a power amp with a Preamp that does input selection and volume control.

Ref 20 is A+F+S
For a long time we have been using OpAmp just like everybody else. A high quality OpAmp circuit can be very good, as used also by many reference amps. But you can't tune the sound. So if you want to sound like tube, then you have to use transistors with tube characteristic. But unlike a tube what is one big transistor with all its good and flaws, we can do a lot with class D and transistors.
Ref 20 wasn't meant to sound like tube.
A Full Bridge class D power stage is more expensive but has an edge over Half Bridge design. So ST-10 and Ref 20 use Full Bridge design.
Switching Power Supply has to be used for so much power density.

I think what we are doing is really a revolutionary steps in Class D, not that the technique was not known by some of the most knowledgeable analog engineers. But it is the extensive mix of analog design techniques and class D designs that is ground breaking. You won't hear about magazines talking about this because nobody wants to promote budget amps with super high end designs.

With regards to a two channel K38, I stated that we have no plan, simply because K38 was designed to be the best amp for movies and music. Further more, the sound characteristic of K38 is quite "American". We have equally important customers in France (who have similar taste as the Chinese) that prefer STA-9, or Japanese and Germans who preferred neutral sound. So here lies the difficult of coming out with a STA-10. How do we strike the balance? So for the mean time, go buy K38 :)

Thank you very much for detailed answer!
I plan to buy Ref-20 in the end of this year, even I contacted already with dealer and discussed regarding terms.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eugene on 1 Jun 2016, 04:05 am
I'm reading with much interest this thread. My speakers are the Apogee Full Range and the low frequencies and mid/high frequencies must be driven separately which is done by a crossover. Is there a possibility to build a crossover in this mighty amp? Thanks for the reaction(s).

Eugene
 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 3 Jun 2016, 07:15 pm
Quote
With regards to a two channel K38, I stated that we have no plan, simply because K38 was designed to be the best amp for movies and music. Further more, the sound characteristic of K38 is quite "American". We have equally important customers in France (who have similar taste as the Chinese) that prefer STA-9, or Japanese and Germans who preferred neutral sound. So here lies the difficult of coming out with a STA-10. How do we strike the balance? So for the mean time, go buy K38 :)

Jason,

I can appreciate that you must weigh choices and consumers' preferences when you decide which variation to put into production. Nonetheless, I'm telling you now that I would jump at the chance to buy a two-channel version of the K38 (assuming I don't cave in and purchase an ST-10 or dual STA-9 beforehand). I have until September/October to decide. Hint hint.

Regards,

Michael
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 3 Jun 2016, 07:18 pm
Oops! Double post.  :duh:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 3 Jun 2016, 09:20 pm
Quote
My speakers are the Apogee Full Range and the low frequencies and mid/high frequencies must be driven separately which is done by a crossover. Is there a possibility to build a crossover in this mighty amp? Thanks for the reaction(s).

It can be done but doesn't make sense from a commercial point of view. We have to design products that are appealing to most people. In any case, you normally have crossover(s) as input to the amp for active speaker configuration.

Quote
Nonetheless, I'm telling you now that I would jump at the chance to buy a two-channel version of the K38 (assuming I don't cave in and purchase an ST-10 or dual STA-9 beforehand). I have until September/October to decide. Hint hint.

The sound of K38 comes from the preamp stage which has 8 channels combined, even though the amp module is 2 channels. So it is not that straight forward to make a stereo amp and we have to redesign the preamp stage. And then put into production bla bla bla, and four months would be gone. So, it would be better off if we just design a new preamp stage (probably between K38 and ST-10 sound) and pick the class-D stage from one of the amps.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 3 Jun 2016, 09:28 pm
My question: my preamp is a Tortuga LDR, which produces an extremely fast, clean, and refined sound - and then warmth is added in my mono tube amps. I prefer clean and fast over warmth, but do you think replacing my tube amps with the ST-10 would render the sound too lean in my set up? I know it's all a matter of personal preference but I am interested in your thoughts. Thank so much!
I think ST-10 will be just the right balance for you. STA-9 will sound too warmth for your liking.
I can't emphaisze enough that everyone should refer to the amp comparison guide. It was created with the input of the chief engineer who designed all these amps.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 3 Jun 2016, 09:52 pm
The sound of K38 comes from the preamp stage which has 8 channels combined, even though the amp module is 2 channels. So it is not that straight forward to make a stereo amp and we have to redesign the preamp stage. And then put into production bla bla bla, and four months would be gone. So, it would be better off if we just design a new preamp stage (probably between K38 and ST-10 sound) and pick the class-D stage from one of the amps.

I think ST-10 will be just the right balance for you. STA-9 will sound too warmth for your liking.
I can't emphaisze enough that everyone should refer to the amp comparison guide. It was created with the input of the chief engineer who designed all these amps.

I do understand. I just wanted to let you know others are interested. In all likelihood I will purchase an ST-10 because I'll pair it to a tube preamp and separate DAC. The power of the dual STA-9 is seductive, but it may be too warm sounding.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 3 Jun 2016, 10:52 pm
The sound of K38 comes from the preamp stage which has 8 channels combined, even though the amp module is 2 channels. So it is not that straight forward to make a stereo amp and we have to redesign the preamp stage. And then put into production bla bla bla, and four months would be gone. So, it would be better off if we just design a new preamp stage (probably between K38 and ST-10 sound) and pick the class-D stage from one of the amps.

I do understand. I just wanted to let you know others are interested. In all likelihood I will purchase an ST-10 because I'll pair it to a tube preamp and separate DAC. The power of the dual STA-9 is seductive, but it may be too warm sounding.

Michael,

So the STA-9 is supposed to be warmer than the IDA-8? You own the  IDA-8 correct? How warm do you think that amp sounds?

I'm also running a tubed preamp and have tried a few solid state amps, with a couple of them being class D. The issue I'm having is the upper midrange on up. It's always a bit harsh with some music. Some of the amps I've tried warm up the mids but they don't do anything for upper mids and highs. Hard to make a decision from looking at a warmth chart so was hoping for some input from you or others that own these amps.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JeffB on 3 Jun 2016, 11:12 pm
I read this whole thread with great interest because somehow I misread the initial price of the K38 as $300.
Darn it.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JackD on 4 Jun 2016, 12:04 am
Greg and Michael

I have run the ST-10 with both the W4S STP-SE  and now the Modwright LS-100.  In both cases the DAC in the chain was the Aqua La Voce S2.  Both of these are very good combinations with the Nola KO's and their combined 8 tweeters. The edge would go to the combo of the ST-10 and the Modwright.  Just for fun I temporarily tried the IDA-8 in this system replacing the Modwright and the ST-10. I still used the Aqua DAC. This combo was far to warm for me.  The IDA-8 in my case has worked the best with the Golden Ear Triton 5 which can be slightly forward if paired with the wrong amp/preamp combo.  If the STA-9 is in that direction I don't think it would be to my liking.  I find the ST-10 to be pretty much neutral and don't find it lean in any way. 

Jack
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: James Romeyn on 4 Jun 2016, 02:18 am
My friend is at the show.  I shall request he visit.  He has the $10k Bricasti M1 SE DAC, and like many of us, is not often impressed.   

This really makes me want to hear the STA-9. My objection to SMPS is based on reliability more than on sonics.

I saw two Hypex Ncore NC400 BTL mono (400/800/1200W @ 8/4/2 Ohm, 1 Ohm minimum), each amp powered by one Hypex SMPS1200A400 (1200W).  Someone shorted both speaker outputs of the two above amps for about thirty seconds.  Absolutely no damage resulted, not even a blown PS fuse.

I can't imagine anything more bullet proof.  Certainly SMPS are not inherently unreliable.   

Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: mresseguie on 4 Jun 2016, 04:51 am
Gregfisk and JackD,

How are you guys doing?

Let's see if I can say all the things I want to, answer questions, and not get chastised for hijacking John's original post. [Brace yourselves. This is going to be long.]

First about the IDA-8:

I've had it now for almost nine months. I've powered Fritz LS/5-R (83.5dB) two-ways in Taiwan and GR Research LGKs while we are traveling the States this year. Oh, yeah. It briefly powered my Jeff Bagby designed Adelphos speakers (87dB) very nicely. I must admit that I really like this amp. It is easy to use; it's got super connectivity options; its size makes it very easy to bring along, and it's got enough power to drive most speakers loudly enough for my needs. This is Nuprime's entry-level amp for crying out loud. My only complaint about it is that it is underpowered for my LS/5-R speakers - and we all know that is not a 'problem'. It simply means I paired the wrong speakers to this amp (or visa-versa). The IDA-8 can produce decent volume with the LS/5-R speakers, but there's not enough oomph to make them sound 'right'. The LGK speakers sound terrific powered by the IDA-8. They are well matched. The same holds true for my Adelphos speakers - well matched.

Just how warm is the IDA-8?

Well, I have a difficult time answering this. It is warmish sounding, but I got to audition a good quality Taiwanese made integrated EL34 tube amp while I was in Taiwan. The two amps sounded completely different. The tube amp sounded amazing. Guitar, piano, vocals, snare drums(!!) ....I finally got why folks go gah gah over tube amps. My AVA 400R doesn't do that and the IDA-8 doesn't do that like the EL34 did either. Aren't EL34 amps 'warm'? Anyway, I must admit I spend a lot of time listening to female vocalists, guitar, cello, Jazz and other music that sounds especially good on warm sounding amps. Is this because this music sounds especially good on my IDA-8, or is it that I simply prefer this music?

Soon after my wife and I returned to Oregon, I spent a wonderful evening at Aldcoll's (Alan) house. He hosted a small G2G. In preparation for this G2G, I requested an ST-10 and a DAC-10H from John; two DACs from Tommy of Digital Amplifier Company; and a passive preamp from Tortuga Audio (never did get the preamp/don't know why). One of the participants brought over his South Korean made Waversa DAC plus a couple other components to pair with it. I brought my IDA-8, my 400R, my AVA T8 tube preamp,  my Rythmik F12G sub, and a bottle of Kavalan Single Malt Solist Sherry Cask Whiskey - 59% alc. Alan presented a Modwright amp (150w/ch??), an Iliana(sp?) preamp, Daedalus Audio Pan speakers (awesome!) and my Gustard X20u DAC that he had kindly taken delivery of while I was still in Taiwan. [Poor guy had to break it in for me for nearly two months. I'm sure it was a terrible burden. ;-)]

We had a small mountain of equipment. I got to hear the ST-10 paired to the DAC-10H, to my X20u, and to the DAC DACs. The DAC-10H/ST-10 sounded great, clear, non-fatiguing. The ST-10/X20u sounded a tad bright, but the sound stage was huge. [Turns out the X20u had been set to a 'forward/aggressive' setting, but we didn't try it with the more laid back setting. :duh:] The DAC DACs lost to all the other DACs - small sound stage/SQ not up to the other DACs IMHO. The DAC-10H/ST-10/AVA T8 combination and the X20u/ST-10/AVA T8 combination sounded 'right' to my ears. I loved all the music that was played. It was warm, beautiful midrange, solid bass, and clear highs.

I had to return the DAC-10H and the ST-10 to John, so I decided to hand deliver them since my wife and I were going to be in LA for a couple days anyway. Once at John's man cave, we spent a few hours listening to the K38 powering the new Evoke Eddie speakers. A DAC-10H was used in this setup. The combination sounded amazingly good. Unfortunately, everything was new to me. The room, the speakers, the amp were all strange to me, so I cannot sit here and tell you which part influenced my experience. I just know it all sounded fantastic.

JackD,

I think I got to hear much of what you hear with your amp/preamp/DAC combination. I know different manufacturers/different sounds, but essentially the same. Based on my above experiences, I want the ST-10. The only thing holding me back is the worry that even the ST-10's 150watts won't be enough to make the LS/5-R speakers sing the way they want to sing. This is why I asked Jason about making a two-channel K38 (more power). It's also why I wonder about the dual STA-9 amps (massive power). I suspect that the dual STA-9 amps will just be too warm for me if paired to the X20u and a tube preamp (probably going to buy a new tube preamp soon).

I brought my IDA-8 to the States with the intention of selling it in September after my wife and I return to Oregon. That may not happen now. The more I use it while we travel, the more I appreciate its potential, its convenience, and all-round high quality. If I don't sell it, I'll give it to my 24-year-old son to 'care for it'.

Gregfisk,

If you're still reading this....I see you live in the great PNW. I expect to drive through your area in the first few days of September. I will still have my IDA-8 as long as it isn't stolen during our travels. Do let me know if you want a short listen....

Have I answered all the questions, babbled enough, and not irritated the lords of this circle?

Quick thought: I think I answered my own question about which amp I want. I'll get the ST-10 unless <by some miracle> I can con Jason into manufacturing an new two-channel K38. Oh, Jason... :thumb:

Regards,

Michael
Currently in Albuquerque, NM.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JackD on 4 Jun 2016, 05:22 am
Michael

I think the ST-10, which was actually tested at 195 wpc by a German magazine, will be more than enough for your Fritz speakers.  The combination of it, the X20U and a good tube preamp will be a really good set-up.  Which tube preamp is another question and will be determined by how much you want to spend and if you want new or used.  I have owned Odyssey amps since 1999, but never an Odyssey preamp.  I think the Candela, new or used, would be a good option. There is one that has been for sale for a couple of months on another site that I have resisted as I have too many as is.  I am also intrigued by the Backert Labs Rhumba though twice as much.  There is a member here and on another site that is using the X20U with the ARC REF-5 and the Nord amps and really likes the combo with VSA speakers.  Again SS DAC, tube preamp to Class D amp.  Another option unless smitten by the Fritz speakers is to try the 60 day demo from Spatial on their open baffle speakers.  I really like mine and the number of owners on this site grows on an almost daily basis.  With them you can run almost any amp you like.  I ran mine for a while in the main room with an EL-34 amp. Once you find the spot you want to settle in and have a budget in mind the possibilities are endless.

Jack
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: dr.sah on 6 Jun 2016, 12:24 pm
is there any inside picture of mch k38?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: dspringham on 8 Jun 2016, 06:01 pm
Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 8 Jun 2016, 06:18 pm
Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...


Hello, D -


I just bought the K-38 and had heard the STA-9 as well...  Jason explained this BRILLIANTLY in a previous post in case you didn't happen to see it... Here it is copied. I'm sure JC will be able to add his thoughts - but we both referred to this a lot at THE Show...


Mark


"After consulting with the chief engineer, I have more details and very interesting information.
[/size][/size]A class-D amp product is consisted of three main components:[/size]Preamp Stage, Class D Stage, Power Supply(note that this Preamp Stage is not the volume control preamp, but an integral front-end of the Class D amp design)Preamp Stage design is made of (A) Op Amp  or  discrete transistors and in NuPrime's designs there two types: (B)ULCAM (Ultra Linear Class A Module) and (C)SECAM (Single Ended Class A Module)Practically all the amp products on the market use Op Amp for preamp stage. Only a few very high end products use discrete transistors design.  This is hard core analog design.  Tube or solid state amp is basically one BIG (giant size) transistor.  Now you can see why we could reproduce tube or solid state sound, while keeping the advantage of class D speed and dynamic. Class D power stage design can be Half Bridge (H) or Full Bridge (F)Power supply can be Switching (S) or Linear (L)Now here's where things get really interesting.IDA-16 =  A+H+S  (Op Amp + Half Bridge + Switching)  for clean, fast, and powerfulST-10  =   A+F+L  for clean, fast, smooth and refinedIDA-8 =  B+H+L  for a little more warmth and fastSTA-9 = C+H+L  for tube-like sound, warmth, and fastK-38 = C+B+H+S   There are more combinations that we can do here:  C+H+S  or  C+B+F+L  or C+B+F+SChief engineer said there could be literally unlimited number of topologies using transistors for the preamp stage, but to get something good is very tedious work.  I think NuPrime is the only company in the world that can offer this type of ultra high end custom design at budget price.We plan to introduce Custom Audio (rack mount) very shortly for customers who order large number of channels (> 10) to do custom selection.  For example, you might want to have 10 channels of IDA-16 and STA-9 combo sound, but only need 50W per channel (multi-room high end back ground music).  We can mount the preamp stage of STA-9 with the Class D power stage of IDA-16, and one 500W SMPS.  Or if you are a speaker company, we can custom design amp module for your active speaker."
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 9 Jun 2016, 03:15 am
Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...

This is what I would like a comparison of, even thou I don't need the power output of the K-38 or the STA-9 as bridged monos. 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 9 Jun 2016, 03:23 am
This is what I would like a comparison of, even thou I don't need the power output of the K-38 or the STA-9 as bridged monos.


I didn't think the power was needed too - until I hear it.  So I heard 100 watts then 200 and then 400 (rough numbers)... None of them were louder - well the two larger ones were - but the point was the dynamic capability. And there is / was much more "weight" in the delivery of the music. So is it needed - that's up to you. I can only speak of EDDIE - he sounds better with the 200 and 400 watt amps.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 9 Jun 2016, 06:06 am

I didn't think the power was needed too - until I hear it.  So I heard 100 watts then 200 and then 400 (rough numbers)... None of them were louder - well the two larger ones were - but the point was the dynamic capability. And there is / was much more "weight" in the delivery of the music. So is it needed - that's up to you. I can only speak of EDDIE - he sounds better with the 200 and 400 watt amps.

I do get what you are saying, I have heard that with my 86db speakers in spades before. I'm now only running the top end of another pair of my speakers which consists of a midrange and tweeter and they are 97db efficient.They can run on pretty low wattage amps. But even with them I have noticed a much better grip on the midrange driver with bigger amps. And I do like to crank it up on occasion and that's when I really notice it.

I suppose if the amps sound good enough it doesn't matter how big they are, then it comes down to what you think you need or how much you want to spend.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 9 Jun 2016, 02:14 pm
I do get what you are saying, I have heard that with my 86db speakers in spades before. I'm now only running the top end of another pair of my speakers which consists of a midrange and tweeter and they are 97db efficient.They can run on pretty low wattage amps. But even with them I have noticed a much better grip on the midrange driver with bigger amps. And I do like to crank it up on occasion and that's when I really notice it.

I suppose if the amps sound good enough it doesn't matter how big they are, then it comes down to what you think you need or how much you want to spend.


Yes, Greg - I failed to add that high current amps don't always have high wattage ratings. And I don't want to make an absolute statement, but from my experience that plays a major role in speaker performance - especially with your 97 db efficiency! If you have some time google around for some high end powered studio monitors and you can see what kind of power they use for woof / mid / tweet. It's very interesting.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jonbee on 9 Jun 2016, 02:39 pm
I have a stack of ST-10 and DAC-10H arriving today. I'll be comparing it in stages to my NAD M51/tweaked N-Core NC-400, which uses no preamp other then the M51.
I love the sound I have now, with no reservations at all on sound quality, but the features of the NuPrime stack, including analog inputs, a headphone amp, 12V system trigger, small size and price make it an appealing package for me.
If I "break even" on sound quality I'll call it a win.
Should be interesting. I'll try to report my initial findings this evening.

 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: MttBsh on 9 Jun 2016, 02:46 pm
I have a stack of ST-10 and DAC-10H arriving today. I'll be comparing it in stages to my NAD M51/tweaked N-Core NC-400. Should be interesting.

jonbee - I am about to order an ST-10 also, please share your impressions when you get a chance! Thanks
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 9 Jun 2016, 03:59 pm
Waiting for Casler's reply regarding comparison of K-38 to bridged and unbridged STA-9...

Hi dspringham,

I think we talked on the phone "pre-show", so my memory is foggy, and I couldn't find any of your previous posts on the STA-9.

But I did see that you are looking for the transparency and detail.

I have heard the STA-9, the ST-10, and the K-38.

In my system, the K-38 and the ST-10 are the "detail" champs. 

That said, the STA-9 is not necessarily "less detailed", but slightly less forward.  I still hear the same highs, but they are slightly further back in the soundstage.

And of course, the STA-9 has the warmer tube-like sound with more even order harmonics.

Let me know if I missed anything we discussed as 5 day at the show fried my brain :scratch:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Hugh on 9 Jun 2016, 04:34 pm
I've got to stop by your place for a listen. :)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: dspringham on 9 Jun 2016, 10:34 pm
Thanks John,

Yep, that was me (from Canada) you spoke with the other week.

I've been considering the ST-9 and 10 and have decided to pick-up a (preowned) DAC 10-H/ST-10 stack. My speakers (Daedalus Audio) are non-aggressive in the top end and slightly towards the warm side of things so I thought the neutrality and resolution of the ST-10 would be a good match. Also, I already have an excellent digital front end (Sony HAP-Z1ES with RWA Stage 3 mods) with battery powered tube output stage with which I will feed the analogue input of the DAC 10. The smoothness of the tubes should be a good match for the high resolution ST-10.

I only wish the DAC 10 had a balanced analogue input so I wouldn't have to do an external balanced/single-ended adapter at the output of my source.

Looking forward to trying the Nuprime DAC section as well.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jonbee on 10 Jun 2016, 12:55 am
Just got the ST-10/10H and am checking 'em out!
I swapped my newly arrived ST-10 for my tweaked N-Core NC-400 for starters. I'm powering my Von Schweikert VR-5 HSE, a 91 db/m sensitive 4 ohm design. First up, I'm using my NAD M51 DAC as source, w/ Zenwave D4 balanced ICs.
 I'm very pleased with the sound. There are clearly differences in sonics- the N-Core has a more forward top end- it pushes the detail a bit more. The ST-10 has a more relaxed sound overall, with a detailed yet easy top end. Detail is very close; the N-core might have a small edge, with a bit more air on top, but the more forward upper range could be responsible for that. The bottom end of the ST-10 is similarly deep and powerful, but I give it the edge in control, which is remarkable as the N-core is the best I've had in that area.
The overall impression of the amp is very enjoyable- it lets the sonic fabric through with a very natural sounding soundstage. Very nice indeed. Certainly in the same class as the N-Core, but with a different, more relaxed flavor.
I just moved the 10H into place, and it is a great match for the amp, perhaps better synergy than the NAD. Very detailed and open; great soundstage depth and width. Very clean bass. Once again, an easier sound than I had with the M51/N-Core. I think a little bit more air and silkiness at the very top would be an improvement, but that is really nitpicking. The more I listen to the combination the more I admire the really wonderful soundstage presentation and overall tonal balance. The music is just plain enjoyable.  Very cool remote, too.
I'm very pleased. As always, matchups are key to this hobby, but this combination is very satisfying, and at a very attractive price. The best, cost-no-object? I'm sure not, but these deliver the goods with very little getting in the way of the music.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jonbee on 10 Jun 2016, 02:58 am
My speakers (Daedalus Audio) are non-aggressive in the top end and slightly towards the warm side of things so I thought the neutrality and resolution of the ST-10 would be a good match.
I owned DA-RMA v2 last year, and I think they will work very well with these. I think they are sonically of the same cloth. The ST-10 is not warm but offers a very natural, unforced view of the music.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JackD on 10 Jun 2016, 03:05 am
jonbee

I completely agree with your assessment of the ST-10 so fair.  Mine is singing happily with my Nola KO's fronted by the Modwright LS-100.  I ran it briefly in the other system with the DAC-10 and the Spatial M3 Turbo S's and it sounded fine there too.  A really good pair of components at a fair price.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: dspringham on 10 Jun 2016, 03:44 pm
jonbee,

Looking forward to your impressions of the DAC-10H in view of the fact that you have your old standard NAD M51 up for sale.

With your DAC 10 comments can you also provide the details of your digital source and how you are connecting (USB, SPDIF etc.)

Regarding your ST-10/ncore 400 comparison, you mentioned the ncores had been modded (Ric Schultz cap mod). How do you think the ST-10 would compare to a stock NC400 (I know this might be straining your auditory memory).

Can you also comment on the DAC 10/ST-10 "stack"  as a complementary pair in terms of SQ, versatility and functionality. It seems to me that they represent a high value package.

Regards,
Dave

WHOOPS! Didn't see the most  recent comments in your modified post. Thank you
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: dspringham on 10 Jun 2016, 03:53 pm
jonbee,

One other thing. Are you running balanced or single ended to the ST-10?

Also, have you tried running the M51 fixed outputs to the DAC-10 in order to assess the analogue throughput of the DAC-10?

Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jonbee on 10 Jun 2016, 04:45 pm
jonbee,

One other thing. Are you running balanced or single ended to the ST-10?

Also, have you tried running the M51 fixed outputs to the DAC-10 in order to assess the analogue throughput of the DAC-10?
Balanced.
No, just used the variable outputs of the NAD.
Still listening happily. This is a great stack. I do think there is synergy to be had with the 2 units together.
NuPrime's claim of superior soundstage depth and width is certainly true. Just huge. My earlier thoughts on the top end may be premature. Compared to the N-Core they are more relaxed on top, but the N-Core always seemed just a bit bright to me, so maybe the NuPrime is just right? I'm sure they will be here a long time. They sure check off all my boxes.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jonbee on 13 Jun 2016, 11:42 pm
Just an update- I've listened to the ST-10/10H for a few days, an I do like it better than the NAD M51/modded N-core Nc-400 I'd been happily using for the last 3 years. The tonality of the ST-10 is equally detailed but more laid back on top than the N-Core, which necessitated I turn up the ambience tweeters on my Von Schweikerts a bit, but the upper mids are more relaxed and natural on the ST-10. I should note that the VSs are a little laid back on their own, so this observation wouldn't necessarily apply to other speakers. Bass range is a bit better defined, too. No downside I've heard.
I still like the N-Core a lot, and moved it to my office, where it sounds great.
The N-Core cost about $2200 in parts, plus my labor. At $1600 the ST-10 equals or betters it and is the biggest amp bargain I've heard, and with the 10H it offers really fine performance that may well be impossible to beat for the $.
It's hard to imagine it being that much better modded, but I'm thinking about the TDSS upgrades. More later if I do that.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 13 Jun 2016, 11:47 pm
Just an update- I've listened to the ST-10/10H for a few days, an I do like it better than the NAD M51/modded N-core Nc-400 I'd been using. The tonality of the ST-10 is more laid back on top than the N-Core, which necessitated I turn up the ambience tweeters on my Von Schweikerts a bit, but the upper mids are more relaxed and natural on the ST-10. Bass range is a bit better defined, too. No downside I've heard.
I still like the N-Core a lot, and moved it to my office, where it sounds great.
The N-Core cost abut $2200 in parts, plus my labor. At $1600 the ST-10 at least matches it and is the biggest amp bargain I've heard, and with the 10H it offers really fine performance that is hard to match for the $.
It's hard to imagine it being that much better modded, but I'm thinking about the TDSS upgrades. More later if I do that.

It may be possible that "some" of that quality you like is due to a higher carrier frequency (around 550khz-600khz) of the NuPRIME.

I looked around, but didn't see the stat for the N-core.  Have you read anywhere what it is?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jonbee on 13 Jun 2016, 11:57 pm
No, I've not.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 14 Jun 2016, 12:18 am
Jonbee, for reference have you tried a Crown XLS 1500 in your system? I have and found the top end and upper midrange harsh but was hoping for a comparison to get a better feel for the upper frequencies of the ST-10.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: srb on 14 Jun 2016, 12:31 am
It may be possible that "some" of that quality you like is due to a higher carrier frequency (around 550khz-600khz) of the NuPRIME.  I looked around, but didn't see the stat for the N-core.  Have you read anywhere what it is?

From the Hypex datasheets, the switching frequencies are:

 Module        Min            Typ          Max   
----------------------------------------------
NC400      470kHz      480kHz     530kHz

NC500           -           450kHz         -

NC1200     440kHz      480kHz     520kHz


Steve
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: MttBsh on 14 Jun 2016, 12:33 am
Just an update- I've listened to the ST-10/10H for a few days, an I do like it better than the NAD M51/modded N-core Nc-400 I'd been happily using for the last 3 years. The tonality of the ST-10 is equally detailed but more laid back on top than the N-Core, which necessitated I turn up the ambience tweeters on my Von Schweikerts a bit, but the upper mids are more relaxed and natural on the ST-10. I should note that the VSs are a little laid back on their own, so this observation wouldn't necessarily apply to other speakers. Bass range is a bit better defined, too. No downside I've heard.
I still like the N-Core a lot, and moved it to my office, where it sounds great.
The N-Core cost about $2200 in parts, plus my labor. At $1600 the ST-10 equals or betters it and is the biggest amp bargain I've heard, and with the 10H it offers really fine performance that may well be impossible to beat for the $.
It's hard to imagine it being that much better modded, but I'm thinking about the TDSS upgrades. More later if I do that.

Thanks jonbee for the update. After reading your impressions of the ST-10 I've decided I need the amp too. Thanks for taking the time to share your findings!
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 14 Jun 2016, 12:51 am
From the Hypex datasheets, the switching frequencies are:

 Module        Min            Typ          Max   
----------------------------------------------
NC400      470kHz      480kHz     530kHz

NC500           -           450kHz         -

NC1200     440kHz      480kHz     520kHz


Steve

Thanks Steve, I had heard around 450kHz, but never had seen the spec
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gammajo on 14 Jun 2016, 03:03 am
I have been enjoying my Nuforce (now Nuprime) Reference 20 monos for over a year. I think my equipment is good enough to hear differences. Speakers Von Schweikert VR 55 acktive ($60,000 and multiple Best In Show, Golden ear and Editors choice awards), Cables all Delphi Ultra ($40,000) Front end is Ayon CD 5s with NOS tubes). The Ref 20 beat all amps tried in my system which were many and to my ears all other I have heard in other systems including big name and reputation class A. It also beat my modded Ref 9V3se and from feedback beats the Ref18 by a small but significant degree in finesse, liquidity, detail, and dynamics.
I would love to hear my 20's against the current amp in discussion. My 20's I think are helped by my tubed preamp. I would guess that this new design adds a touch warmth and perhaps bloom that I get from my tubed pre to the neutral (not cold) Ref 20.
Indeed Nuprime is great bang for the buck, but beyond that creates provides a total cure for upgraditis if the rest of the system is up to the same standard.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: MttBsh on 14 Jun 2016, 03:22 am
I would love to hear my 20's against the current amp in discussion.

According to Nuprime, the ST-10 (current amp in discussion) is virtually identical in sound to the reference 20, it just has considerably less power. The question is, given a low wattage system and high efficiency speakers, would there be any sonic benefit in selecting the ref 20 over the ST-10?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 14 Jun 2016, 06:28 am
As the power exceeded a certain level, the design has to change. Cost goes up exponentially instead of linearly as power goes up.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 14 Jun 2016, 07:56 am
As the power exceeded a certain level, the design has to change. Cost goes up exponentially instead of linearly as power goes up.

If you were answering MttBsh's question, which I was hoping you would, I personally didn't get the answer. So, the design had to change, did it change the sound? A lot of us don't need all of the power but still want the quality of sound. I'm personally sold once I get a handle on the differences between going with (2) ST-9s or the ST-10. I too run a really good tube preamp which adds a quality to the music I have never had with SS preamps or any other tube pre for that matter. I've tried several SS amps in my system, class ab, b, bd and d and have been most happy with the Butler 2250 which is a hybrid amp with one tube per channel on the output stage. I still feel like the upper freq. are a bit hard but the midrange is very nice. If I could find an amp that could smooth out the upper mids and highs I would stop looking for amps and start spending money on other parts of my system like a new dac or roon with HQplayer running on my mac mini.
Title: iZotope RX-5 Hum
Post by: maty on 14 Jun 2016, 08:20 am
"I still feel like the upper freq. are a bit hard but the midrange is very nice..."

You need a good soft equalizer.

(http://maty.galeon.com/WP-imagenes/soft/iZotope-RX-5-De-Hum-65-130-18000.png) (http://maty.galeon.com/WP-imagenes/soft/iZotope-RX-5-De-Hum-65-130-18000.png)

Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 14 Jun 2016, 08:33 am
If you were answering MttBsh's question, which I was hoping you would, I personally didn't get the answer. So, the design had to change, did it change the sound? A lot of us don't need all of the power but still want the quality of sound. I'm personally sold once I get a handle on the differences between going with (2) ST-9s or the ST-10. I too run a really good tube preamp which adds a quality to the music I have never had with SS preamps or any other tube pre for that matter. I've tried several SS amps in my system, class ab, b, bd and d and have been most happy with the Butler 2250 which is a hybrid amp with one tube per channel on the output stage. I still feel like the upper freq. are a bit hard but the midrange is very nice. If I could find an amp that could smooth out the upper mids and highs I would stop looking for amps and start spending money on other parts of my system like a new dac or roon with HQplayer running on my mac mini.

Since ST-10 and Ref 20 amps have different designs (they do come from the same topology), they will sound different (but close). How close?
See the Amp Comparison chart.  I said that many times in all the topics. The Amp Comparison chart is the gold standard and you should treat it like a spec.  This chart was debated and discussed with engineering and also based on listening test. So it is the best we can offer.

But keep in mind that the differences between these amps are quite small.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eugene on 14 Jun 2016, 11:55 am
Hi Rustydoglim, thanks for your reaction on my question. I have another question. For driving my speakers the lf and mf/hf needs separate amp's. If I use 2 K38's with bridged channels for full power, two bridged channels of each K38's will not be used. Is this a bad thing for this amp? Thanks, Eugene
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gammajo on 14 Jun 2016, 12:46 pm
GregFisk The  later Nuforce/Nuprime amps are very revealing so all things that can make the treble hot or harsh need to be addressed such as tweeter design, room reflections, cables, source and vibration control. With these correct, then the Nuforce/Nuprime designs to me are beautiful in the highs - detailed, liquid, fast, and natural and I am very sensitive to any glare, tizziness or imbalance in the highs, for example cymbels and bells sound correct in attach, body and decay and upper violins are natural with correct bite but not grating. Hope this helps
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: S Clark on 14 Jun 2016, 01:00 pm
. If I could find an amp that could smooth out the upper mids and highs I would stop looking for amps and start spending money on other parts of my system like a new dac or roon with HQplayer running on my mac mini.
Since you are already familiar with and like what hybrids offer, you might look at Moscode.  When they come available used, they are usually reasonably priced, and are quite musical in their mids and highs. 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: jonbee on 14 Jun 2016, 02:05 pm
Jonbee, for reference have you tried a Crown XLS 1500 in your system? I have and found the top end and upper midrange harsh but was hoping for a comparison to get a better feel for the upper frequencies of the ST-10.
No, haven't heard it. The open, smooth, natural mids and highs as well as the very powerful, clean bass are the elements of the ST-10 that stand apart. Refinement and slam.
Last night I watched the James Taylor at Beacon Theater dvd, which has been a standard of mine for sound quality which I often come back to. Sony made it a showcase for their recording technology at the time, pulling out the stops. I've never heard it sound so good, from top to bottom, front to back. Just wonderful.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 14 Jun 2016, 02:44 pm
Hi Rustydoglim, thanks for your reaction on my question. I have another question. For driving my speakers the lf and mf/hf needs separate amp's. If I use 2 K38's with bridged channels for full power, two bridged channels of each K38's will not be used. Is this a bad thing for this amp? Thanks, Eugene

Not at all, the front panel has the on/off buttons for each channel. You just turn off the unused channels.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eugene on 14 Jun 2016, 03:08 pm
That's great to hear. Now I will look for a home demo arrangement to find out the remarkable qualities of this amp.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: gregfisk on 15 Jun 2016, 02:57 am
I want to thank all of you who answered my questions and gave me sound advice. It is very much appreciated, now I just need to make a decision on what amp(s) I will buy.

If anyone has any other input of their personal comparisons between the ST-9 or ST-10 regarding the upper frequencies I would love to here them. Otherwise I will probably just take a leap of faith and pick one.

Thanks again for all the input.

Greg
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Tubegem on 26 Jun 2016, 05:43 pm
Not at all, the front panel has the on/off buttons for each channel. You just turn off the unused channels.
Going on the opposite direction, any chance we will see a 3 channel version of this amp (K-33) with both balanced and un-balanced inputs. 
 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 26 Jun 2016, 05:55 pm
I will think about making something more flexible.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rajacat on 26 Jun 2016, 07:00 pm
It would be great if NuPrime would develop an amp with integrated DSP similar to what  the Crown XLS 1502 offers.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 26 Jun 2016, 07:43 pm
It would be great if NuPrime would develop an amp with integrated DSP similar to what  the Crown XLS 1502 offers.


Hello, Rajacat -


I was looking at the Crown features. Are you looking at the NuPrime for a pro application? I rarely see those kind of features on an audiophile amp. Less is more typically. What's your perspective - I'm curious...
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rajacat on 26 Jun 2016, 08:17 pm
No this wouldn't be for a pro setup. It would be for bi-amping diy speakers, so to eliminate the need for an external dsp, associated cables and passive crossover. As you say, simplify...simplify. :)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: dr.sah on 30 Jun 2016, 11:52 am


found it on russian web page.

(http://www.audiocircle.com/image.php?id=146037)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: reillyzing on 1 Jul 2016, 02:01 am
Is the MCH K38 overkill with Spatial M3 Turbo S speakers?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: audioguy213 on 1 Jul 2016, 02:07 am
Is the MCH K38 overkill with Spatial M3 Turbo S speakers?
do you have eight of them?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Evoke on 1 Jul 2016, 02:14 am
No this wouldn't be for a pro setup. It would be for bi-amping diy speakers, so to eliminate the need for an external dsp, associated cables and passive crossover. As you say, simplify...simplify. :)


You're absolutely right. I use it to bi and tri-amp speakers I develop. It's so versatile. I've been using it lately in bridged mode (400 watts/ch) for a new little 2-way with a 5" mid-woof. 400 is overkill for that  :duh:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: reillyzing on 1 Jul 2016, 02:30 am
do you have eight of them?
Eight channels aside... I mean, are the Spatials capable of showing off most of the K38's abilities reasonably well?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JackD on 1 Jul 2016, 02:59 am
With the Spatial's you are perfectly fine with the ST-10 and keep the cost difference in your pocket for something else.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: reillyzing on 1 Jul 2016, 03:02 am
With the Spatial's you are perfectly fine with the ST-10 and keep the cost difference in your pocket for something else.
Thank you
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 1 Jul 2016, 04:45 am
Is the MCH K38 overkill with Spatial M3 Turbo S speakers?

Strangely enough, I just had a gentleman with whom I was discussing the ST-10 for the Spatial M3 Turbo's that Clayton told him he would be better off with 400wpc??????

The specs say as little as 5wpc will drive them.

Go figure.

But if this fellow was in any way accurate (I think Clayton also sells a 500wpc amp) then the K-38 "bridged" would meet even those outlandish assertions.

That said, again I would defer to JackD, who actually has tried the ST-10 with them, and felt the ST-10 quite capable.

So is it "overkill"?  Well, in the fact that you would (or could) bi-amp with 400wpc x 2 into each speaker with what I have stated is the best amp my ears have heard.

But again, you would likely never explore the advantages in dynamics and SPLs, so you might be in the overkill territory (although it would be glorious)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: zybar on 1 Jul 2016, 10:14 am
Strangely enough, I just had a gentleman with whom I was discussing the ST-10 for the Spatial M3 Turbo's that Clayton told him he would be better off with 400wpc??????

The specs say as little as 5wpc will drive them.

Go figure.

But if this fellow was in any way accurate (I think Clayton also sells a 500wpc amp) then the K-38 "bridged" would meet even those outlandish assertions.

That said, again I would defer to JackD, who actually has tried the ST-10 with them, and felt the ST-10 quite capable.

So is it "overkill"?  Well, in the fact that you would (or could) bi-amp with 400wpc x 2 into each speaker with what I have stated is the best amp my ears have heard.

But again, you would likely never explore the advantages in dynamics and SPLs, so you might be in the overkill territory (although it would be glorious)

I have Spatial Audio M3 Turbo S speakers and they sound fantastic with a 45 watt or 800 watt amp.

Given their high sensitivity, it isn't necessarily pure SPL's, but more about the transient peaks.

I would buy/use whatever amp sounds best to you.

Good luck.

George
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eric Gustafsson on 7 Jul 2016, 09:04 pm
What happened with the comparsion with STA-9 in bridged mode?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Letitroll98 on 7 Jul 2016, 09:34 pm
Yes, and I'd like to know more about the differences in circuit design between the STA-9, ST-10, and K38 amps.  I've read the amp comparison chart, but would like to know why the ST-10 has better soundstaging, detail and dynamics than the STA-9.  Is it the power supply, the chip, sampling frequency, what makes the difference in sound quality?
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 7 Jul 2016, 10:31 pm
Yes, and I'd like to know more about the differences in circuit design between the STA-9, ST-10, and K38 amps.  I've read the amp comparison chart, but would like to know why the ST-10 has better soundstaging, detail and dynamics than the STA-9.  Is it the power supply, the chip, sampling frequency, what makes the difference in sound quality?

Not sure if you saw this chart or not, but it pretty much gives you the primary differences:

<<<<<<<
A class-D amp product is consisted of three main components:
Preamp Stage, Class D Stage, Power Supply (note that this Preamp Stage is not the volume control preamp, but an integral front-end of the Class D amp design)

Preamp Stage design is made of
(A) - Op Amp or discrete transistors with two difference NuPrime designs:
(B) - ULCAM (Ultra Linear Class A Module) or
(C) - SECAM (Single Ended Class A Module)

Practically all the amp products on the market use Op Amp for preamp stage. Only a few very high end products use discrete transistors design. Discrete transistors design is costly and challenging to accomplish.

Class D power stage design can be Half Bridge (H) or Full Bridge (F).
Power supply can be Switching (S) or Linear (L).

Below is an illustration of how we created the unique sonic characteristic for each product:

IDA-16 = A+H+S (Op Amp + Half Bridge + Switching) for clean, fast, and powerful sound

ST-10 = A+F+L for clean, fast, smooth and refined sound

IDA-8 = B+H+L for a little more warmth and fast

STA-9 = C+H+L for tube-like sound, warmth, and fast

K-38 = C+B+H+S for the best sonic characteristic suitable for watching movies and listening to music.

>>>>>>>



As you can see, the ST-10 and the STA-9 have different combinations.

Hope that offers a bit of info for you.

Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Letitroll98 on 8 Jul 2016, 01:39 am
Thanks John, I had seen that post before, but only read it carefully today.  Unfortunately I can't see any correlation between the use of different driver stages, power stages, and power supplies and the amplifier comparison chart.  Of course I'm sure there's a good reason why some amps have either half or full bridged power stages or switched mode versus linear power supplies, it just doesn't match up in the order of the amp comparison chart.  The driver stages almost line up, but not quite.  So I'm thinking there must be either something I'm missing or it's not so much the design type, but the implementation of the technology.  It's a little look inside that implementation that I was looking for.  And to get the post back on track with the thread, how does that all work for the K 38?  It doesn't match anything.  :icon_lol:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 8 Jul 2016, 08:25 am
Quote
Unfortunately I can't see any correlation between the use of different driver stages, power stages, and power supplies and the amplifier comparison chart.
I suggest that users ignore the technical details and just focus on the Amp Comparison chart. Off course you can't correlate fully because it is not as simple as assembling lego blocks to get certain result. What we have shown is the concept.

Forget about the WHY, just follow the recommendation.

For example, if you are a circuit design engineer, then you would know the trade offs between Full Bridge and Half Bridge circuit. If you don't, this is not the forum for circuit design, and I am certainly not qualified to explain. Similarly, how challenging is using discrete transistor to create the desire sonic characteristic? What we have explained here (preamp stage, Class-D amp stage, switching PSU, linear PSU and various trade offs) are known to circuit design engineers, but very few would be able to achieve the kind of control, precision and performance that we have done here. An analogy would be "we all know how to drive a car, but few can win the Indy500".

I have a master degree in electrical engineering, but major in computing. And I can only understand half of what my chief engineer is telling me (may be half is a big exaggeration). I do understand how a transistor works, and have done simple design with transistor (long time ago), But what he has done is really hard.

I met a German speaker designer at the high end show in Munich in May. He doesn't know how it works, but he is smart enough to buy the STA-9 and IDA-16, take the preamp stage of STA-9 and combine it with the power amp module in IDA-16, and created a new sound and he told me it is incredible. I guess he doesn't want as much warmth as STA-9, and also not as neutral as IDA-16. Bingo.

So imagine if one day we can let you customise your sonic characteristic comfortably at home by flipping a few switches, everything is so smooth, so powerful, so dynamic, so perfect and yet customisable. Did I just describe audio heaven? Hopefully we will get there in less than 5 years time. And it will be affordable.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: drumnman2 on 8 Jul 2016, 02:12 pm
What happened with the comparsion with STA-9 in bridged mode?


Yes I am interested in this also if you have had the time. I know you said after "The Show"
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: John Casler on 8 Jul 2016, 10:26 pm

Yes I am interested in this also if you have had the time. I know you said after "The Show"
What happened with the comparsion with STA-9 in bridged mode?

Hi Guys, If you are talking about my evaluation, it is still coming.

It was my intention to do it after the show, but we ended up having to let the show attendees take the Show Samples and then the orders taken then and after the show left us in a back order position (everyone was ordering the STA-9 in pairs).

So luckily one pair just came back as someone decided to go with the MCH K-38 instead.

As soon as I receive them back, I should be able to spend a little time comparing.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Letitroll98 on 9 Jul 2016, 12:33 am
I suggest that users ignore the technical details and just focus on the Amp Comparison chart. Off course you can't correlate fully because it is not as simple as assembling lego blocks to get certain result. What we have shown is the concept.

Forget about the WHY, just follow the recommendation.

For example, if you are a circuit design engineer, then you would know the trade offs between Full Bridge and Half Bridge circuit. If you don't, this is not the forum for circuit design, and I am certainly not qualified to explain. Similarly, how challenging is using discrete transistor to create the desire sonic characteristic? What we have explained here (preamp stage, Class-D amp stage, switching PSU, linear PSU and various trade offs) are known to circuit design engineers, but very few would be able to achieve the kind of control, precision and performance that we have done here. An analogy would be "we all know how to drive a car, but few can win the Indy500".

I have a master degree in electrical engineering, but major in computing. And I can only understand half of what my chief engineer is telling me (may be half is a big exaggeration). I do understand how a transistor works, and have done simple design with transistor (long time ago), But what he has done is really hard.

I met a German speaker designer at the high end show in Munich in May. He doesn't know how it works, but he is smart enough to buy the STA-9 and IDA-16, take the preamp stage of STA-9 and combine it with the power amp module in IDA-16, and created a new sound and he told me it is incredible. I guess he doesn't want as much warmth as STA-9, and also not as neutral as IDA-16. Bingo.

So imagine if one day we can let you customise your sonic characteristic comfortably at home by flipping a few switches, everything is so smooth, so powerful, so dynamic, so perfect and yet customisable. Did I just describe audio heaven? Hopefully we will get there in less than 5 years time. And it will be affordable.

Thanks for the reply Jason.  I understand what you're saying and accept your explanation.  I like the story about the German and the idea of a configurable amp.  Keep us posted.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Early B. on 9 Jul 2016, 01:05 am
So imagine if one day we can let you customise your sonic characteristic comfortably at home by flipping a few switches, everything is so smooth, so powerful, so dynamic, so perfect and yet customisable. Did I just describe audio heaven? Hopefully we will get there in less than 5 years time. And it will be affordable.

You just described tube rolling. :lol:

In the auto industry, you can go online, choose all of the features you want, and your custom car will be delivered to your door. Wouldn't it be nice to do the same thing on your website for audio gear at a reasonable price? Perhaps that's where Letitroll98 was headed -- how can a layman determine the right configuration for him based on sonic attributes? Yeah, as you mentioned, it's much more complicated than that, but the engineer's job is to un-complicate it.

A few years ago, I owned a couple of Audio GD solid state components whereby you could change the sonic character by choosing from various low cost, plug-in modules. Worked very well, IMO.     
Title: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 1 Aug 2016, 08:38 am
Today I will go from two STA-9, used as mono blocks, to an MCH-K38. I will use it in a bi-wire setup with 4 channels in bridged mode.  :drool:
Title: Re: MCH-K38
Post by: mresseguie on 1 Aug 2016, 03:57 pm
I look forward to your impressions.  :thumb:
Title: Re: MCH-K38
Post by: Eisener Bart on 1 Aug 2016, 04:59 pm
Today I will go from two STA-9, used as mono blocks, to an MCH-K38. I will use it in a bi-wire setup with 4 channels in bridged mode.  :drool:

:banana piano:
Title: Re: MCH-K38
Post by: Eric Gustafsson on 1 Aug 2016, 07:04 pm
I must say that STA-9 is a very good amp, but to compare them with K38 is ridiculously. K38 is much much better at everything.
I use K38 bridged to 4 channels. 2 channels at 400 W each to each speaker. My speakers, Magnepan 3.3/R, seems to like the power (2 x 800 W) from K38.
So far the K38 is giant killer!  :notworthy:

I will give you more feedback later. Now I have to listen to more music.
Title: Re: MCH-K38
Post by: John Casler on 2 Aug 2016, 10:20 pm
I must say that STA-9 is a very good amp, but to compare them with K38 is ridiculously. K38 is much much better at everything.
I use K38 bridged to 4 channels. 2 channels at 400 W each to each speaker. My speakers, Magnepan 3.3/R, seems to like the power (2 x 800 W) from K38.
So far the K38 is giant killer!  :notworthy:

I will give you more feedback later. Now I have to listen to more music.

This is exactly true.

In a sea of wonderful amps the STA-9 is a STAND-OUT especially for it's price point.

That said, the K-38 rises to a level that made me post my glowing assessments.

While everyone knows ALL amps and impressions are based on many elements including listener's preferences, if we look at all the qualities that make a truly great amp, the K-38 will be in the CREAM of "price no object" gear.

Some will have them in their systems and NEVER even know how good they are, because just assuming that an 8 channel amp for HT is not of that quality, and never actually listen closely.

Have fun Eric!
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 5 Aug 2016, 07:18 pm
There is a minor 50 Hz hmmmmm when K38 is connected via xlr-cables. Connected via rca-cables is silent.
Something wrong with my xlr-cables or anything else?
Title: Re: MCH-K38 - a giant killer!
Post by: Eisener Bart on 5 Aug 2016, 07:20 pm
There is a minor 50 Hz hmmmmm when K38 is connected via xlr-cables. Connected via rca-cables is silent.
Something wrong with my xlr-cables or anything else?

I had same with one STA-9. Then I found that is XLR cable.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 5 Aug 2016, 07:27 pm
Very strange. I didn't have this problem with STA-9 with same cables.
I have to try with some other xlr-cables.
Title: Re: MCH-K38 - a giant killer!
Post by: John Casler on 5 Aug 2016, 09:25 pm
Very strange. I didn't have this problem with STA-9 with same cables.
I have to try with some other xlr-cables.

What preamp are you using?

Try this:  while using the XLR cables as you are, take a single RCA cable and run it from any RCA output of your preamp to any input of the K-38.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 5 Aug 2016, 10:32 pm
My preamp is from Hattor Audio in Poland.
I will test the trick with the rca-cable
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 6 Aug 2016, 08:58 am
To connect an rca cable didn't solve the problem. I will test with som other xlr cables.
Title: Re: MCH-K38 - a giant killer!
Post by: Eisener Bart on 6 Aug 2016, 03:20 pm
I will test with som other xlr cables.

Yes, it's better idea.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 8 Aug 2016, 08:46 am
Now I have tested with some other xlr cables, but with the same 50 Hz hmmmmmm sound.  :bawl:

What to do?  :dunno:
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 8 Aug 2016, 08:25 pm
If your K38 has humming noise with XLR cable, please get help from our support. We can fix it. Create a Help Desk ticket on mytdss.com.
If you are not from USA or Canada, email support@nuprimeaudio.com
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 8 Aug 2016, 08:42 pm
I have now sent an e-mail to support as I live in Sweden.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 9 Aug 2016, 07:25 pm
By coincidence I found this information today.

"Due to the XLR shield and ground pin specification (see https://en.wikipedia.org/wiki/XLR_connector), some manufacturers implement it differently from others, therefore there could be humming noise if a non NuPrime product is connected to MCH-K38 using XLR cables.
XLR Hum Eliminator products from http://www.ebtechaudio.com/hedes.html can be used to completely remove the noise and improve performance."

It seems to me that Nuprime has made some kind of special xlr connection in MCH-K38. It can' t the same as in STA-9. Why? This is not good at all!  :nono:

I found the information in the FAQ releated to Home Theater and not in the Power Amp section.  :duh:

Now I have to spend money on one or several "Hum Eliminators".  :icon_twisted:

Title: Re: MCH-K38 - a giant killer, but watch up!
Post by: rustydoglim on 10 Aug 2016, 12:41 am
There is no need to do that anymore. We have to replace a board on the MCH-K38.
We just need to get the instruction and board for you. No soldering is needed to replace the board.
Title: Re: MCH-K38 - a giant killer, but watch up!
Post by: Eric Gustafsson on 10 Aug 2016, 05:11 am
There is no need to do that anymore. We have to replace a board on the MCH-K38.
We just need to get the instruction and board for you. No soldering is needed to replace the board.

That sounds great! When will it happen?

So far I haven't heard anything from your support. Not even a notice that they have recevied my e-mail.
Title: Re: MCH-K38 - a giant killer, but watch up!
Post by: loonix on 10 Aug 2016, 07:03 pm
@rustydoglim

I was thinking about purchasing this from SonicUnity and wondering if they will have these new boards installed? Is there another/better source in the US to get a unit?

@Eric, thanks hoping to get a detailed review in the coming days! While you wait to test out XLR, maybe we can also get some feedback from you utilizing the unbalanced inputs.  :thumb:
Title: Re: MCH-K38 - a giant killer, but watch up!
Post by: dwaleke on 10 Aug 2016, 08:51 pm
I contacted John Casler on the forum here.  He can get an updated unit.
Title: Re: MCH-K38 - a giant killer!
Post by: John Casler on 11 Aug 2016, 12:02 am
By coincidence I found this information today.

"Due to the XLR shield and ground pin specification (see https://en.wikipedia.org/wiki/XLR_connector), some manufacturers implement it differently from others, therefore there could be humming noise if a non NuPrime product is connected to MCH-K38 using XLR cables.
XLR Hum Eliminator products from http://www.ebtechaudio.com/hedes.html can be used to completely remove the noise and improve performance."

It seems to me that Nuprime has made some kind of special xlr connection in MCH-K38. It can' t the same as in STA-9. Why? This is not good at all!  :nono:

I found the information in the FAQ releated to Home Theater and not in the Power Amp section.  :duh:

Now I have to spend money on one or several "Hum Eliminators".  :icon_twisted:

Initially we discovered this issue with the Yamaha CX A5100 PrePro and it seemed isolated to just that component.  The suggestion to use the Ebtech isolator was put up, because the user found that totally took care of the problem.

Apparently the engineers found a "fix" in a snap in replaceable board.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 12 Aug 2016, 05:45 am
Apparently the engineers found a "fix" in a snap in replaceable board.

Maybe on the drawing board. So far I haven't heard anything more.  :evil:
Title: Re: MCH-K38 - a giant killer, but watch up!
Post by: Eric Gustafsson on 12 Aug 2016, 06:49 am
Now things are moving a little bit forward.  :D
Title: Re: MCH-K38 - a giant killer, but watch up!
Post by: flat4 on 13 Aug 2016, 05:18 pm
Now things are moving a little bit forward.  :D

Good to hear. Please keep us posted. This is on my short list for my next amp purchase down the road.
Title: Re: MCH-K38 - a giant killer, but watch up!
Post by: Eric Gustafsson on 21 Aug 2016, 09:09 am
Waiting............... :sleep:
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 26 Aug 2016, 06:16 am
New board is on its way!  :D
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 31 Aug 2016, 01:01 pm
The new board has arrived to my office :D, but I'm on business trip until friday. :(
Title: Re: MCH-K38 - a giant killer!
Post by: nocrapman on 31 Aug 2016, 09:31 pm
Wonder how they will sound with LX521s. Maybe its time to build a pair.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 2 Sep 2016, 08:21 pm
This evening I have installed the new board, but there is still a 50 Hz humming noice.  :cry:
What to do?
Title: Re: MCH-K38 - a giant killer!
Post by: Eisener Bart on 3 Sep 2016, 10:11 am
This evening I have installed the new board, but there is still a 50 Hz humming noice.  :cry:
What to do?

ask dealer to replace it or money back.
Title: Re: MCH-K38 - a giant killer, but ..........
Post by: Eric Gustafsson on 3 Sep 2016, 01:02 pm
It seems to me that the difference between the boards is that two links has been replaced with two resistors. I couldn't see any other difference.
I have an ongoing dialog with Nuprime, Hattor Audio (the manufactorer of my preamp) and the dealer how to solv the problem.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JimW on 5 Sep 2016, 09:19 am
I'm considering the NuPrime MCH-K38 but on one dealer site SNR is listed as < -80dB, which doesn't seem acceptable to me, but on the NuPrime site it's listad as SNR < -95 dB which isn't that great either, someone want to enlighten me?

Thanks

J



Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: JimW on 5 Sep 2016, 01:30 pm
Only a 1 year warranty   :nono: . Most amps are at least 3 years if not 5. Wyred 4 Sound 5 years, Emotiva 5 years.

That is a deal breaker for me.



 
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: srb on 5 Sep 2016, 03:34 pm
I'm considering the NuPrime MCH-K38 but on one dealer site SNR is listed as < -80dB, which doesn't seem acceptable to me, but on the NuPrime site it's listad as SNR < -95 dB which isn't that great either, someone want to enlighten me?

It's listed as > 80dB in the Specifications section of the downloadable Manual as well.
MCH-K38 Manual (http://www.nuprimeaudio.com/index.php/products/downloads/send/20-mch-k38/28-mch-k38-pdf-manual.html)
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eric Gustafsson on 5 Sep 2016, 03:59 pm
I'm considering the NuPrime MCH-K38 but on one dealer site SNR is listed as < -80dB, which doesn't seem acceptable to me, but on the NuPrime site it's listad as SNR < -95 dB which isn't that great either, someone want to enlighten me?

Thanks

J

My suggestion is that you listen to the amp instead of reading technical data.  :thumb:
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eric Gustafsson on 5 Sep 2016, 04:02 pm
Only a 1 year warranty   :nono: . Most amps are at least 3 years if not 5. Wyred 4 Sound 5 years, Emotiva 5 years.

That is a deal breaker for me.

Here in Sweden is it 3 years warranty on products from Nuprime.  :D
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: Eric Gustafsson on 5 Sep 2016, 04:06 pm
It's listed as > 80dB in the Specifications section of the downloadable Manual as well.
MCH-K38 Manual (http://www.nuprimeaudio.com/index.php/products/downloads/send/20-mch-k38/28-mch-k38-pdf-manual.html)

According to this page http://www.nuprimeaudio.com/index.php/products/amplifiers-and-preamps/multi-channel-amps/mch-k38.html (http://www.nuprimeaudio.com/index.php/products/amplifiers-and-preamps/multi-channel-amps/mch-k38.html) is it 95 dB.
Title: Re: The BEST AMP I have EVER heard (at ANY price) has 8 channels!
Post by: rustydoglim on 5 Sep 2016, 05:31 pm
I think MCH-K38 warranty should be 2 years, the manual has an error. In some countries it has 3 year warranty.
Title: Re: MCH-K38 - a giant killer, but ..........
Post by: rustydoglim on 5 Sep 2016, 06:31 pm
We are waiting for engineering to look into this issue.  XLR pins implementation could be different between European and US standards as I showed you on the Wikipedia info.  But now you have already tried two preamp boards with different XLR pins implementation and still have the ground noise. That would be very strange.
And your RCA connections do not have noise.
So this points to ground loop problem with MCH and your preamp.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 8 Sep 2016, 07:53 am
I have now changed to my "old" preamp with only unbalanced output and the sound is amazing. I can't understand how Nuprime can make such a wonderful amp at that price level.  :notworthy:

Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 8 Sep 2016, 08:08 am
Nuprime has been very very helpful and supporting in order to solve the humming problem. Of some reasons the Hattor Audio preamp and Nuprime MCH-K38 doesn't like each other. It is like us. Some people doesn't get along and many times we just have to accept that and leave each other.

As it looks now I will keep the MCH-K38 for looooooong time and the preamp from Hattor Audio will be sold. It's a great passive preamp together with other power amps.
Title: Re: MCH-K38 - a giant killer!
Post by: John Casler on 8 Sep 2016, 05:35 pm
I have now changed to my "old" preamp with only unbalanced output and the sound is amazing. I can't understand how Nuprime can make such a wonderful amp at that price level.  :notworthy:

And THAT sir, is why I started this thread.  :thumb:

While one's sonic preferences can be all over the board, there is no denying that for some reason(s) this amp is special in the way it delivers.

Very glad you enjoy it.

I might add, that the DAC-10 is also a great and reasonably priced "sonic mate" to the K-38

Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 8 Sep 2016, 05:43 pm
And THAT sir, is why I started this thread.  :thumb:

You didn't start this thread. It was someone else.  :wave:
Title: Re: MCH-K38 - a giant killer!
Post by: John Casler on 8 Sep 2016, 05:49 pm
You didn't start this thread. It was someone else.  :wave:

LOL. . . what a dummy I am.  I thought this was the thread I started some time ago.

Looks like "you" started this one and I'm glad you did.

Thanks for keeping me straight  :lol: :lol: :lol:
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 9 Sep 2016, 08:10 pm
I merged John's topic and this topic into one now so that new comers can read the feedbacks on MCH-K38.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 22 Sep 2016, 05:54 am
This amp just get better and better.  :D I just love the power and the dynamic in the amp.  8)

Yesterday I heard something I never ever heard before. I was playing Pink Floyd´s Money and there is an fantastic guitar solo in the first part. At least I have always thought that it´s an guitar solo, but it´s not. As far as I heard it´s two guitar playing the "solo".

I don't understand how NuPrime can make such an excellent amp for that kind om money!  :thumb:
Title: Re: MCH-K38 - a giant killer!
Post by: John Casler on 22 Sep 2016, 08:42 pm
This amp just get better and better.  :D I just love the power and the dynamic in the amp.  8)

Yesterday I heard something I never ever heard before. I was playing Pink Floyd´s Money and there is an fantastic guitar solo in the first part. At least I have always thought that it´s an guitar solo, but it´s not. As far as I heard it´s two guitar playing the "solo".

I don't understand how NuPrime can make such an excellent amp for that kind om money!  :thumb:

Totally agree, and that is why I made such a commotion a few weeks ago raving like crazy about it.

Many might pass this amp by, because it has 8 channels, and the general line of thinking is it is "just" a HT amp.

IMO it is much more.  :thumb:

Title: Re: MCH-K38 - a giant killer!
Post by: bummrush on 22 Sep 2016, 09:26 pm
So do they have a 2 chanel amp that has the magic????
Title: Re: MCH-K38 - a giant killer!
Post by: John Casler on 22 Sep 2016, 09:52 pm
So do they have a 2 chanel amp that has the magic????

Depending on the "sound" you like, ALL the NuPRIME Amps have "Magic".  (remember I am a dealer  8))

There is not a 2 channel version of this exact configuration. 

Title: Re: MCH-K38 - a giant killer!
Post by: gammajo on 22 Sep 2016, 11:39 pm
Just spent an hour re-reading this entire thread from the beginning - there is a lot of complex but excellent information in it. worth the read from the beginning if you are just joining
Title: Re: MCH-K38 - a giant killer!
Post by: Armaegis on 23 Sep 2016, 06:12 am
So do they have a 2 chanel amp that has the magic????

If you bridge outputs and bi-amp your speakers... that's sort of like 2 channels  :green:
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 23 Sep 2016, 09:35 am
Just in case anyone learning about MCH-K38 for the first time, note that this is a Class A+D hybrid design, so don't expect it to run very cool like a pure class-D amp. And we have 1KW of power supply going into 8 channels so it will feel hot even when idle. Our goal is explosive dynamic and yet retain the audiophile quality at quiet listening level.
Title: Re: MCH-K38 - a giant killer!
Post by: kevb on 23 Sep 2016, 11:02 am
I am putting this on my short list as my dream amp.  Love  my STA-9 and IDA-8 and what they can do, but this would absolutely be all I need to power 2 systems at once - I have 2 systems in my main room, one digital based system firing widthwise, and one analog based system firing lengthwise.

This could power both systems at once - with 400 wpc of sublime NuPrime power!   :thumb:   Only issue is it is way outside my budget at this point...   :(
Title: Re: MCH-K38 - a giant killer!
Post by: mervinpearce on 23 Sep 2016, 03:41 pm
Got this amp and in storage with the AVP... will listen to in when I am back in my country but boughtt it as I have the IDA-8,IDA-16, 2 x STA-9 bridged with DAC-9... and now a HPA-9 (no idea as I will llisten in a month or two).  Best buy with NuPrime.
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 27 Sep 2016, 05:30 pm
We need to start special loyalty membership group for this kind of customer!
I am working on a new membership site so that we can provide better service and offer extra perks (free extended warranty for example, trade in program) to customers.
Title: Re: MCH-K38 - a giant killer!
Post by: Eric Gustafsson on 27 Sep 2016, 06:16 pm
If you bridge outputs and bi-amp your speakers... that's sort of like 2 channels  :green:

That's how I use my MCH-K38. It gives a lot of power for each speaker and an increadible sound.
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 27 Sep 2016, 06:49 pm
Wonder how they will sound with LX521s. Maybe its time to build a pair.

I have a pair driven by 2 Emotiva xpa-5 gen 2 amps..one per side...using asp so 4 amp channels per side. Looking to try the K38 too soon as my distributor can get one in for demo. Another option might be 4 sta-9’s

In the mean time I'm going to try a lexicon dd8 I scored the other day...but that's more likely destined to go on my lxminis unless the sta9’s get there too...I just sold a pair of sat-9’s to a client for another lxmini build

I wonder @jason can the K38 run into 2 Ohm loads in bridged mode or normal mode?
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 1 Oct 2016, 07:40 am
I wonder @jason can the K38 run into 2 Ohm loads in bridged mode or normal mode?

No problem with 2 Ohm load in either mode.
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 1 Oct 2016, 10:31 am
No problem with 2 Ohm load in either mode.

That great news...is the GAIN the same too @ 22dB ... which is rather low as I would have expected somethinling closer 26-29dB

Does this gain also apply to other Impedance settings? and other models like STA-9 / 10, IDA-8 etc?
Title: Re: MCH-K38 - a giant killer!
Post by: triumph on 1 Oct 2016, 11:59 am
Just got the MCH-K38 home and been listening for two hours.... but it's evening and I can't even try pushing it a little!

What I like so far is the presentation.  Even at low volume, which my old Yamaha couldn't do.  All the details would get sucked out at low volume with the Yamaha amp.  The MCH brings it all back, even at such low volume. 

Can't wait for tomorrow!  :)
Title: Re: MCH-K38 - a giant killer!
Post by: Eisener Bart on 1 Oct 2016, 05:21 pm

What I like so far is the presentation.  Even at low volume, which my old Yamaha couldn't do. 

it's familiar feature of NuPrime PowerAmps. i had same effect with STA-9.
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 19 Oct 2016, 08:48 am
I have just received the K38 from my local distributor for a period of testing with the www.LinkwitzLab.com LX521 Reference (ASP) and LXmini/Studio with MiniDSP 4x10HD setups so will report back how it sounds and any issues with the rather low input gains that are being talked about (22dB) plus will be testing with some other box speakers. Mostly will be using PS Audio DS Jr or Oppo HA-1 DAC setups, but might have to add in preamp if the gain setup is not going to give enough headroom.
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 20 Oct 2016, 03:44 am
On the Linkwitz forum another member asked me

"Having checked out the NuPrime amp, the gain listed on the spec sheet is "x22" which I'm taking to be "voltage gain". The resulting dB gain should be a more ideal 26.85dB. Since you own the amp and I'm just reading the spec sheet, it would be interesting to know if it's voltage or dB gain."

@rustydoglim Jason would you be able to elaborate on the gain for this model, and also if there is any difference between the RCA and BAL inputs gain. And for that matter the STA-9 for which I have in a different setup with LXmini and MiniDSP 2x4

I guess I could get out a signal generator and measure it but thats a lot of messing around for what should be detailed in the specs.
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 20 Oct 2016, 03:58 am
Adding this a separate post...

The K38 is a beast...its images on the website belittle its heft and size to say the least. I was quite surprised at the size, not to say its huge, rather that it looked larger than I expected from the web site images, but the big surprise was the weight!!! And the external build quality is superb. Well done NuPrime - I am looking forward to seeing how this compares with the existing 2 x Emotiva Gen 2 XPA-5's it will potentially replace...granted its 3-4 times the price, for 8 as opposed to 10 channels.

I use it as an 8 channel amp - 4 channels for each speaker (Bass,Bass,Mid,Tweeter) in an active setup detailed here http://www.linkwitzlab.com/LX521/Description.htm and my build here http://walaneh.com/LX521/

I might just relegate the XPA-5's to HT channels duty and use the Linkwits setups exclusively for stereo use...they currently are the L/R for the HT setups.
Title: Re: MCH-K38 - a giant killer!
Post by: triumph on 20 Oct 2016, 08:08 am
zwizardofoz,  what do you use for preamp/ DAC with the MCHK38?
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 20 Oct 2016, 08:27 am
Is an Active crossover front ended with a PS Audio DS Junior or via an Emotiva XMC-1

(http://walaneh.com/xpl/xpl-000113.jpg)
Title: Re: MCH-K38 - a giant killer!
Post by: smishsmorshen on 20 Oct 2016, 08:27 pm
Adding this a separate post...

The K38 is a beast...its images on the website belittle its heft and size to say the least. I was quite surprised at the size, not to say its huge, rather that it looked larger than I expected from the web site images, but the big surprise was the weight!!! And the external build quality is superb. Well done NuPrime - I am looking forward to seeing how this compares with the existing 2 x Emotiva Gen 2 XPA-5's it will potentially replace...granted its 3-4 times the price, for 8 as opposed to 10 channels.

I use it as an 8 channel amp - 4 channels for each speaker (Bass,Bass,Mid,Tweeter) in an active setup detailed here http://www.linkwitzlab.com/LX521/Description.htm and my build here http://walaneh.com/LX521/

I might just relegate the XPA-5's to HT channels duty and use the Linkwits setups exclusively for stereo use...they currently are the L/R for the HT setups.

Looking forward to your review/impressions. Currently on the fence with getting the K38 or the new gen3 XPA-7..
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 11 Nov 2016, 11:07 am
I cant comment on the xpa-7 G3 but it's not as flexible as the k-38 with the later having bridgable adjacent channels and of course an extra channel to boot.

My application was using 4 channels per speaker via an active crossover Pre amp inputs with speakers connected directly i.e. No internal speakers crossovers...well for the most part but there was a simple capacitor -inductor crossover as the mid range is covered by 2 drivers.

My main issue was the temperature that the k38 idles at when on or even when there is no signal. Way over what I would expect for a d class but maybe it's the class a inputs that's driving up the temp.
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 11 Nov 2016, 08:30 pm
MCH-K38 is a hybrid A+D design. The idling power is 40W (with all 8 channels turned on).  You save a few watts per channel by turning some of them off.
Title: Re: MCH-K38 - a giant killer!
Post by: zwizardofoz on 12 Nov 2016, 02:37 am
I'm forced to run in a non aircon room where the ambient temp when I'm not listening is up around 28 C. Thus having to get around the back to turn it off is not an option.

I think there was a trigger in so would that only put the unit in standby or would that effectively bring the unit to an almost off and not generate so much heat when not being used?
Title: Re: MCH-K38 - a giant killer!
Post by: srb on 12 Nov 2016, 04:00 am
As previously stated, the idling power is 40W with the amplifier powered on and all 8 channels active, but with no input signal.

Standby normally refers to the state where the amplifier circuitry is not active except for the power required to keep the trigger relay circuitry active (and/or in the case of a remote controlled preamplifier or integrated amplifier, the IR or RF receiver circuitry active).

If the amplifier meets European Conformity CE certification, that would be limited to .5W after January 2013, but not seeing any certification logos on the available rear panel photos, it's unknown if it meets that standard.

Steve
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 12 Nov 2016, 08:23 am
It is CE certified. But the EU regulation about the standby power is not part of the CE cert which test for safety and EMI etc.
The standby power regulation has some leeway (I am not exactly sure what it is since I don't manage the certification). What I do know is that for some type of device, the power button is sufficient. Or there are exception for certain class of devices.
Title: Re: MCH-K38 - a giant killer!
Post by: triumph on 23 Dec 2016, 05:14 am
Can the MCHK38 drive a channel at 2 Ohms? 
I'm considering wiring two 4 Ohms subwoofer drivers (that will bring me down to 2 Ohms) to help boost sensitivity, or to be used as 2 mono subs using the same signal.

I've looked online or in the documentation, and I didn't find any information regarding 2 Ohms operation.  It talks about 4 and 8 Ohms, but no mention of 2 Ohms.  Which kinda lets me believe that it won't do 2 Ohms, but figured I'd ask anyway!  :)

Thanks!

And Happy Holidays!
Title: Re: MCH-K38 - a giant killer!
Post by: Evoke on 23 Dec 2016, 05:31 am
Can the MCHK38 drive a channel at 2 Ohms? 
I'm considering wiring two 4 Ohms subwoofer drivers (that will bring me down to 2 Ohms) to help boost sensitivity, or to be used as 2 mono subs using the same signal.

I've looked online or in the documentation, and I didn't find any information regarding 2 Ohms operation.  It talks about 4 and 8 Ohms, but no mention of 2 Ohms.  Which kinda lets me believe that it won't do 2 Ohms, but figured I'd ask anyway!  :)

Thanks!

And Happy Holidays!


Happy Holidays - When you have a subwoofer that quotes 4 ohms, it may actually go lower or higher depending on the frequency. While you can run at 2 ohms (Rusty can confirm) I would never suggest going below 4. And with 8 channels, you can driver each woofer with its' own amp channel. That still leaves 6 for LCR/Surround or bi-amp.


In my case I run 4 channels at 400 watts to bi-amp my stereo speakers. The dynamics are insane. Hope my bit if input helps in some way.
Title: Re: MCH-K38 - a giant killer!
Post by: srb on 23 Dec 2016, 05:32 am
2Ω paralleled load nominal, but if your drivers dip down to 2Ω or 3Ω at some frequency(s), that would be a 1Ω - 1.5Ω load, and it probably can't do that.

Since the amplifier puts out the same power at 4Ω or 8Ω, you could wire them in series for a nice safe 8Ω load.

Steve
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 27 Dec 2016, 04:45 pm
It can work with 2ohm, but now you wire the two subwoofer together, it could go to 1ohm which is not a good idea as it will draws a lot of current from the power supply, you are better off using two channels with two subwoofer separately.
Title: Re: MCH-K38 - a giant killer!
Post by: ZAPHOD2012 on 24 Mar 2017, 03:19 am
my take ....

I have Audience 2+2 in a stereo system in the bedroom, they have been powered by Cary Audio and Parasound multi channels. Due to the weight and only stereo need i sold the Cary and Parasound for the Nuprime ST-10. I was cautious as i have hated my previous experiments with class d amps such as rotel, pioneer and wyred4sound, all cold and lifeless, boring and flat. The ST-10 was a revelation, sweet, very detailed, tight, extended and bouncy, it had life and was a joyful match with the 2+2's, i cannot remember a more enjoyable sound in 30 years, especially for the money, and the mids are incredible. In my main system i needed to replace my hernia weighted Cary 7 channel, so with my positive experience with the ST-10 I plumped for the MCH-K38 at half the weight of the Cary and hoping it would come close to the exceptional ST-10. The MCH-K38 will be used in a 5.1 system driving Audience 4+4's when they arrive from the factory. In 5.1 mode the first 4 channels will be bridged and that is how i compared it to the ST-10, not only did it equal the ST-10 but in bridged mode bettered it. Same family signature but just with a more effortless control, more open, less restrained and detailed, I am extremely surprised and very happy, what a combination made in heaven, the Audience and the Nuprime .... rock on .....
Title: Re: MCH-K38 - a giant killer!
Post by: rustydoglim on 24 Mar 2017, 08:25 pm
Thank you thank you thank you. Customer's validation always bring such joy for all of us at NuPrime.