[gregfisk]

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

[Armaegis]

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??

[rustydoglim]

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.

[rustydoglim]

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.

[timind]

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. 

[maty]

A STA-9 with SMPS 500 or 600 will be a very good idea 

Maybe, Signal to Noise Ratio: < -95dB at 1W, 10W, 100W => with SMPS < -100 or 105 dB

[maty]

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

[Armaegis]

Maty, you think swapping in a DIY power supply is going to sound better than what they designed???

[Wind Chaser]

Anything built to a price point can be improved.

[maty]

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.

[bh46118]

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.   
Risky on the credibility level.

[gregfisk]

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.

[John Casler]

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. 

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. 

But, there are some clear caveats, personal preferences, and needs to consider.

[John Casler]

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.

[John Casler]

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.

[Freo-1]

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

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

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. 

[John Casler]

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. 

[rustydoglim]

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.

[maty]

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).

[Eisener Bart]

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?