What speakers, preamps, etc make the Class D amp sing?

roymail · « **on:** 23 Apr 2010, 10:08 pm »

Well, the Class D amp thread is nearly 70 pages and well over 1300 posts. Many have built this amp and have listened to it in a variety of systems. How about we do some evaluating?

Please give us your impressions along with speakers and other gear you've used with it. What sounds good or not so good when paired with this amp? How does the Class D amp compare to other amps you've used in your system?

I'm hoping this thread will serve as a helpful companion to the original Class D amp thread. This will only happen if you guys all participate. Thanks!

Robert F. · « **Reply #1 on:** 24 Apr 2010, 10:53 am »

The Classdaudio amp is my first separate amp and first amp diy project.
My system so far:
Classdaudio amp 250 watt @ 4 ohm , 125 watt @ 8 ohm CDA-254L kit
Arcam Alpha 9 integrated amp used as a preamp only
Harmon Kardon FL8400 CD player
Kimber Hero cables from CD to preamp
Kimber PJB from Arcam to amp
Kimber 4TC speaker cables
Speakers are DIY Mini-Statements design is here http://speakerdesignworks.com/MiniStatements.html (see gallery)

I like this amp better every time I use it. Sound stage is wide in the horizontal plane and is wider in the vertical plane than what I had before (Yamaha RX-V1400 receiver). I hooked up the Arcam as an amp and the “D” is also better in these regards as well. Imaging is fantastic, however, that also has to do with the speakers ability also. The feeling I get with this amp is “power” the music just seems to come out of speakers with no effort, kind of hard for me to explain that one. I never knew my speakers could have so much good sounding bass. I thought I would add a sub but I don’t need one with this setup. I can feel the bass in the floor ,chair, and the air to some extent. The mids are wonderful. The voices are right there and when vocals are quiet they are clear and when vocals get loud they can be right in your face if that is the intent. Highs are very clear. Some times I get goosebumps with the highs. I listen to Pink Floyd “Time” and the clock chimes are like a wall of sound that can almost be too much to take in. Not that it sounds bad but there is so much intensity going on it can be overwhelming. I never had a Hi-Fi system until now. I only had Mid-Fi in the past and this is a real eye opener for me.
I have found that this amp can be dangerous in that the sound is so clear that I can just turn the volume up a little at a time and before you know it , way to loud, however, I will have a s**t eatin’ grin on my face

Well, that’s my take on my first exposure to the realm of true Hi-Fi.
Next up is some DIY silver interconnect cables and I am going to build the Dodd DIY buffer.

Robert

macrojack · « **Reply #2 on:** 24 Apr 2010, 12:17 pm »

Go Robert!! Your enthusiasm is delightful. You are going to have a fantastic system for relative peanuts once you get your preamp built.

Mariusz · « **Reply #3 on:** 24 Apr 2010, 01:22 pm »

Speakers - DIY back loaded horns with Jordan drivers JX92S
links: Spawn Changs 3 horn plans , Jordan JX92S drivers
Cost:
drivers - $360
MDF - $50 (2 sheets 8'x4')
other - $50
total - $460 (depending on the source and materials used)

Preamp/buffer - Nelson Pass B-1
links - AC thread, DIY built step-by-step instructions and B1 review from enjoy the music & here

price - $150 to $250 and up (depending on options, skills, parts)

DAC - Maverick Audio Tube Magic D-1 ( it can also be used as preamp)
links: AC thread and manufacturer website
price - $200

Source - Logitech Squeezebox Touch
link - manufacturer website

price - $299 (paid $249 shipped)

macrojack · « **Reply #4 on:** 24 Apr 2010, 04:54 pm »

Mariusz - It's your call as to how you want to run this but sometimes you will come across a Cheap and Cheerful product that invites, or even demands, to be mated with much more expensive components. I'm using an ugly little wooden box with a ClassD Audio 60 watt/8 ohm amplifier in it, driven by a $4000 Parasound preamp. This little amp is driving some very high performance and reasonably high dollar horns and sounding like it belongs right where it is.
I'll leave the name of my previous stuff out of this discussion but suffice it to say that the little wooden box stomped it and I've come to prefer it to my mono SET amps as well.

So, is it appropriate to answer this post in this Circle with that kind of gear?

Mariusz · « **Reply #5 on:** 24 Apr 2010, 05:57 pm »

Absolutely !!!!

The system posted earlier was just that. System that Class D amp is used with.
Surely this amp replaced some pricier amps in SOME systems and didn't met expectations in the others.

Because your rig is more on the pricey side it doesn't disqualify you from posting in this circle, thread etc.

This thread is about cheap amp that performs ........ regardless of associated gear.

Quote

I'll leave the name of my previous stuff out of this discussion but suffice it to say that the little wooden box stomped it and I've come to prefer it to my mono SET amps as well.

Wooden box had NOTHING to do with the sound.
Shinny, pretty box does what it does best - it looks good.

Same with women and books.

jtsnead · « **Reply #6 on:** 25 Apr 2010, 05:55 pm »

ClassDaudio SDS254 amp w/ jtwrace case

Speakers - Joseph Audio RM25XL

Preamp - Modwright SWL 9.0SE w/ NOS 7119

Sony SCD-XA5400ES w/ isoclean fuses

Analog - VPI Scout, Trans-Fi T3Pro, Benz Ace SL, Ray Samuels Nighthawk

Cables - Furutech AG-12 Phono, XLO Ref3 interconnect, XLO HTP12 BW speaker cables

Probally going to buy another amp module and run bridged set up

steve k · « **Reply #7 on:** 25 Apr 2010, 10:15 pm »

Good thread, Roy.

I'm running the SDS 224 on the mids and highs and the SDS 258 on the bass panels of my modified Magnepan IIIA's.
Preamp: VTL 5.5 w/ phono stage
DAC: Museatex Bitstream
Transport: Pioneer Elite PD-65
Analog: VPI MK III with Audiomods arm and Grado Reference Sonata
Cables: mixture of BlueJeans and Clarity Labs

As I said in the original thread, I was originally using a pair of VTL MB-125 monoblocks on top and a John Hillig modified Hafler DH 500 on the bottom. Prior to that I used a pair of VTL Deluxe 300's on the bottom.

I've also heard the ClassD 224 with Merlin VSM's and open baffle Lowthers and it worked quite well in both systems. I also heard the 258 in my friend's system with Maggie 1.6's when we did the Wyred4Sound comparison. We heard the Class D with the Wyred4Sounds preamp and also with his Dodd Audio tube preamp. In all these cases, I think the Class D's sound best with tube preamps. The tubes add some warmth and 3 dimensionality to the soundstage that enhances what the Class D's are already doing well. I'm not ashamed at all to say I'm happier with the sound of my system with the Class D's driving it than with any previous amplification,tube or solid stage. I think they are dead quiet, great at extracting low level detail, dynamic, accurate with a somewhat "warm" and enveloping tubelike sound. Again, I've never heard ALL these qualties in one Class D amp until now.

steve

roymail · « **Reply #8 on:** 25 Apr 2010, 10:28 pm »

Thanks for the reports so far. Steve, appreciate the specifics and comparisons. Hope others will do the same and keep it going.

Since the Class D amps are certainly "cheap and cheerful," what I'm hoping for are a variety of comparisons with more costly, popular and well respected amps... like Steve did. However, the intention is not to bash or disrespect anyone else's design.

The comment about Class D amps sounding best when driven by tube amps is the type of input we're looking for. Not everyone may agree, but that's what makes this discussion interesting and helpful.

Thanks to everyone!

Robert F. · « **Reply #9 on:** 28 Apr 2010, 10:38 am »

A little classdaudio system update.
I built my first set of DIY silver interconnect cables the other day and tried them out with the “D” amp yesterday. Cables go from preamp to amp. Kimberly Hero from CD to preamp. Cables are made with 28 gage fine silver (99.999% pure). Wire runs inside 8 gage Teflon jacket. RCA connectors are Dayton RCAGS-ST. I made my cables in the fashion of Tempo Electric Big Twist interconnects.
Soundstage appears to be a bit wider and highs are good. The thing that strikes me the most is the sound that pans from one speaker to the other speaker seems to be a bit smoother. This may be my imagination as I just had to go by memory. Being real or imagined, the sound to me is “better”. I have no proof or no scientific measurements to back that up, however, I like them. Best part is I made these cables myself and the thing I like very much is they are exactly the length I needed. All my main system cables will be DIY from here on out. Going to build another set and replace Hero’s and give it a whirl.

Robert

jtwrace · « **Reply #10 on:** 28 Apr 2010, 11:16 am »

Pics?

Robert F. · « **Reply #11 on:** 28 Apr 2010, 08:29 pm »

Pic's of DIY cables and "guts" of cables.

Robert

Big Red Machine · « **Reply #12 on:** 28 Apr 2010, 10:13 pm »

Is that a stranded wire? Did you use 2 conductors or three? They look nice.

Robert F. · « **Reply #13 on:** 29 Apr 2010, 01:12 am »

Wire is not stranded. Two wires.

Robert

pjchappy · « **Reply #14 on:** 30 Apr 2010, 01:47 am »

Well, here are my first impressions. I got to listen to it today after finally getting the damn thing assembled late last night.

Anyways, I worked from home today (sitting only a few inches behind the sweet spot.

Can't get into the sweet spot while on my PC), so I had several hours with music going. While I did not do any "critical" listening, it was turned up enough to be more than just background music. . .and enough to almost immediately notice some very nice things.

First, a bit of background. . .

My system took a major step forward several months ago after installing several DIY rigid fiberglass panels. I also upgraded my speakers' crossovers a few months ago. I do plan on upgrading my speakers (hopefully fairly soon) and going active with them. That is why I bought this amp. . .and will make another one with the Super Class Ds in a bit. Once I get the Super Class Ds, I will use them to drive my current speakers until my speaker upgrade. . .and then use the normal Class Ds for bass duties and the Super Class Ds for mid/tweet duties (again, for my future speakers).

Now on to my first impressions. . .

When I first started listening, I did notice a few things. I thought maybe they were simply due to the fact the music I had going on had not been played for a very, very long time. . . and had not been played at all yet on my current set-up (minus the Class Ds). This was the remastered Dark Side of the Moon (the redbook version burned to my PC from the SACD/redbook that came out a few years ago). Well, what I heard was. . .simply more detail! However, some things sounded quite harsh at some points (such as the heavy tremolo on the electric guitar on Money). I think I've noticed this before. . .and I think it may have been because I was probably ever so slowing increasing the volume. . . and may have been a bit too much for my monitors? I'll try it again later. This was also early on and I was paying much less attention to the music overall. . .and was doing the opposite later. I haven't had a similar annoyance since, so I would say it was the material and/or speakers as the culprit. As I said, I'll try it again later.

Anyways, due to the fact I hadn't heard this material in awhile and on this set-up, I put on some stuff I have recently listened to: Pink Floyd - The Division Bell; Wilco - Kicking Television; Wilco - A Ghost is Born. David Gilmour - Live in Gdansk. With everything, definitely have noticed better defined bass. I have also (again) just noticed simply more detail/definition. On The Division Bell, I remember noticing a bass line (forgot which song) I remember having that deeper EQ (intentional) sound previously to hearing that same sound, but with a subtle "string" tone to them. I was pretty amazed I never heard that before.

Could all this be due to a quieter background? Maybe/possibly? I don't really care. . .all that matters is I like it so far! (By the way, that Gilmour album (triple CD, 2 DVD version) simply sounds fantastic

).

System:

External HD-->Belkin Pure AV FireWire cable-->Sony VAIO laptop-->Belkin Pure AV USB cable-->Peachtree Audio Nova (used as USB DAC and preamp)-->new, homemade ICs (Canare Star-Quad based, with Canare RCAs)-->Class D amp (CDA-254)-->Bolder M-80 speaker cables-->GR Research Paradox 1s-->My soul

The details of my Class D build can be found here and here.

Looking forward to putting it through its paces this weekend.

Paul

P.S. As I was writing this, I leaned into the sweet-spot, which I can't really be in when I am on my laptop. Definitely more detailed. . .and even a bit of an expanded soundstage. Maybe I'm just noticing a better separation due to more clarity/more detail/less "noise?" I'll have to confirm this weekend. Regardless, so far, so very good!

steve k · « **Reply #15 on:** 30 Apr 2010, 02:00 am »

Congratulations Paul! I think the detail you're hearing is mostly due to the noise floor which is non existent. I"ve noticed in certain systems the dbops can sound a little "bright" but nothing that a little cable management couldn't solve. They're certainly not perfect but I still don't think you can beat them for the price.

Happy tunes!
steve

pjchappy · « **Reply #16 on:** 30 Apr 2010, 02:15 am »

Steve,

We all owe you a big thanks for unleashing these beasts on AC!

I'm truly impressed with these. I did not expect this big of a difference. Regarding the harshness, as I said, it hasn't reared it's ugly head again (yet). We shall see.

I need to make a GAS gathering soon. . .it's been, what, 5 years since I was at your house? Damn, time flies. . .

Thanks again, Steve!

I feel cheap. . .yet cheerful.

Paul

Mariusz · « **Reply #17 on:** 30 Apr 2010, 03:05 am »

Quote

Steve,
We all owe you a big thanks for unleashing these beasts on AC!

+1

Mariusz

roymail · « **Reply #18 on:** 1 May 2010, 06:09 pm »

Anyone using a passive volume control with this amp? If so, was the amp board set to 26db or 32db? I'm assuming it would be 32db.

Any input on this... Thanks!

parodielin · « **Reply #19 on:** 4 May 2010, 05:24 am »

I use Pass B1 preamp and Class D to drive my RS 3 Way TMWW. The combination of Pass B1 and Class D transformed the listening experience. I upgraded from HK 635. Before I finished Pass B1, the HK 635 was the preamp. The difference between Class D and HK 635 was there but not huge. After Pass B1, the magic happened. The combination is simply amazing. My brother in law will finish his Statements Monitors next week. I was eager to try this combo on Statements.