[toxteth ogrady]

Okay, one more 'to do' on my growing 'to do' list. Might as well take care of it now before I put the amp in the case.

[dvenardos]

Digikey, $6.85
http://parts.digikey.com/1/parts/51788-capacitor-10000uf-63v-elect-tsha-eco-s1ja103ea.html

Are these the caps you're referring to? http://www.diycable.com/main/product_info.php?products_id=602&Cid=d267424e09d9ab5452567d828ec78634

[roymail]

My case came out pretty nice, by the way. It's a powder coated par metal case with stainless steel cap screws and a 1" thick faceplate of polished clear acrylic.

Nice front bezel... who cut and polished that thick acrylic?  Good job!

[Nick77]

Digikey, $6.85
http://parts.digikey.com/1/parts/51788-capacitor-10000uf-63v-elect-tsha-eco-s1ja103ea.html

Yup, but out of stock until Feb 2011.

[toxteth ogrady]

Nice front bezel... who cut and polished that thick acrylic?  Good job!

Thanks! Except for the drilling, everything was done at a Tap Plastics store near me. I was going for a modern Scandinavian look but think I ended up with a disco Scandinavian look instead.  

[guest1632]

Yes thats who i bought them from, i purchased only 4 to start with thinking the amp would not respond beyond 40k but the bump to 60k was very favorable.

Well now, ... I knew my bugging you to get the 6 caps would pay off. lol.

So looks like what I need to do is to get the caps, and when I place the order, send Tom the caps, and he can just solder them in in place of the ones he currently uses in his present power supply.

Ray

[Nick77]

Well now, ... I knew my bugging you to get the 6 caps would pay off. lol.

So looks like what I need to do is to get the caps, and when I place the order, send Tom the caps, and he can just solder them in in place of the ones he currently uses in his present power supply.

Ray

Ray i knew you would be relieved. Hehe

[Flounder]

 Hi Everyone

This is an update on the Class D SDS-4 amp saga in my system.

The ultra short answer is -  it is out of the system.

I ran up the hours so I could feel comfortable it was "burned in"

I tried several speaker cables and didn't find a great deal of change.

The four main "issues" are:

1) There is a definate lack of bass depth and to a degree, deliniation of what bass was produced. The Tube gear simply ruled here.

2) This one will be very hard to describe. Through the midrange, it gives the impression that  most of the sounds are  appearing at the same volume level. For example  a guitar solo or lead vocal will be mildly depressed nearly  at the same level as a background instrument. To give a real world example of this - Dire Straits album "On Every Street" track 11  "Planet Of New Orleans" This track has lots of low level percussion going on in the back ground. With  the Class D amp  it gave the perception that  the percussion was almost as loud as Mark Knopfler's vocal and lead guitar   This gave the appearance of enhanced resolution at first but became bothersome after a while. For those questioning which is correct- I have compared this to 3 amps and two completely different sytems and the Class D definately is the different one. I'll allow you to decide as to which is "correct".

At the same time as the mids seem to have "leveled" the sounds the highs are still a bit rolled off as I previously noted. For another real world example, Eva Cassidy "Live at Blues Alley" there isn't the ambience of the hall and low level information that gives the feeling of being at the club listening through pro audio gear. The hum of the tube amps on stage are subdued and not nearly as apparent through the other amps I tried.

4) This one should be no surprise. Tube amps simply have more "presence" and feel more like listening to a living performer/performance. The tube sound stage is bigger , deeper and more detailed.

I really hadn't thought about  #4 until I put the tube gear back in and went "Oh ya that's what was missing" My sister was visiting and she heard the Class D. She commented it sounds nice but not as real as my tube amps she heard the previous visit. That's when I decided to pop the tube gear back in to see if she was right and she was.

Now I still haven't managed to get the other linear power supply board in. I ordered it on Sept 17. Still haven't got it yet. At the  end of the  first week  this month (Oct), I asked whether it was shipped yet, Connex said oh we shipped it a few days ago and I'll get you the tracking #. A week later, they came back  with a tracking # (and I can't find a Hong Kong shipper which recognises that #) and said it's on it's way - you should have it in two weeks.  DIY Hi Fi Supply also based in Hong Kong had stuff to me in 7 days from the time of order. So.......we wait - NOT impressed.

If / when the Power supply board ever shows up I'll put in a comment on how it sounds from the supplied heavy duty board.

I did put in a power conditioner ( Belkin Pure AV PF60) and as others found it really did help the sonics, especially in the sound stage department. It went from the sound hanging around the speakers to having real width and depth. For a $200 buck conditioner I was very impressed.

I never did put in the other monitor speakers so far. Some day when I'm bored I'll do it.

 Before people get the wrong impression, this is in comparison to much more costly tube monoblocks with a complete re-build using premium parts.  I still am amazed at what $400 will buy you today. Even two years ago you'd never get this quality for under a grand at the minimum.

Now it's out of the main system, I'm going to stick it in my set/high efficiency set up -300B amp and DIY Planet Ten Half Changs (Fostex FE207) speakers. Might be fun.

Kevin

[Rocket_Ronny]

Thanks Kevin:

What tube amps and speakers are you running?


Rocket_Ronny

[Flounder]

Hi RR

Sonic Frontiers and Sonus Faber cremonas ( original style not the new MM)

KB

[guest1632]

Ray i knew you would be relieved. Hehe

Hi Nick77,  Sounds like you'd better send your supply to Kevin. His amp seems to suffer from a lack of dynamics. Hmmm, not good. I'm also giving some thought as to whether to get either the ClassD or hugh's amp. Seems for just under a grand, might be a another steal. Not to hijax this thread. i do wonder if the S4 or is it the T4, isn't as good sounding as the s254 or s258 board.

Did you guys see the review of Blair's version of the amp? That too was really good.

So someone had asked if the caps that Kevin has are the same ones that you bought? Anyway, all done now.

Ray Bronk

[Nick77]

I am not at all familiar with the SDS 4 board but it has been mentioned the IR boards sound a little sweeter than the TI version.

[Barry_NJ]

I believe the SDS-4 is first mentioned here...

http://www.audiocircle.com/index.php?topic=76400.msg831007#msg831007

After the above review, I'll be keeping the SDS-258 as my goal.

[roymail]

Did you guys see the review of Blair's version of the amp?

Ray, do you have a link for that review?  Thanks!

[Barry_NJ]

Did you guys see the review of Blair's version of the amp? That too was really good.

Ray Bronk

Ray, do you have a link for that review?  Thanks!

Second, please don't tease...

[jtwrace]

Nothing really that earth shattering IMO.

http://www.stereomojo.com/Niteshade%20SS500%20Amplifier%20Review/NiteshadeSS500Amplifier.htm

of course lets not forget that you can build one from here www.classdaudio.com

[Flounder]

OK I did a very brief audition of the SDS4 amp with my high efficiency speakers using some of the
same disks used with the Cremonas. The brunt of the midrange  problems seem to be ameliorated. It is still there to a small degree but this is now down to the sort of presentation variations you could expect from differing amplifier topologies. The highs are much better with this easier to drive speaker, oddly enough.

I still prefer the 300 B amp  with the major reason being no fault of the SDS4. The designer of the speakers stated to me when I bought the drivers from him that this style of speaker works best with amps that have a low damping factor. He specifically did not recommend class d style amps as they have too much bass damping and this doesn't allow the bass to bloom with the Fostex drivers.

I'm simply going to conclude the SF speaker  /SDS4 amp combination is not a good one.

It will be interesting to hear from others with the same board with different difficult to drive speakers.

This is likely  a one of a kind situation or possibly the SDS4 doesn't play into difficult loads as well as Tom initially thought.

I guess I'll have to get the monitor speakers out now as my curiosity is up. The monitors have a
nominal 6 ohm impedence so they should split the difference nicely.

Kevin

[wushuliu]

OK I did a very brief audition of the SDS4 amp with my high efficiency speakers using some of the
same disks used with the Cremonas. The brunt of the midrange  problems seem to be ameliorated. It is still there to a small degree but this is now down to the sort of presentation variations you could expect from differing amplifier topologies. The highs are much better with this easier to drive speaker, oddly enough.

I still prefer the 300 B amp  with the major reason being no fault of the SDS4. The designer of the speakers stated to me when I bought the drivers from him that this style of speaker works best with amps that have a low damping factor. He specifically did not recommend class d style amps as they have too much bass damping and this doesn't allow the bass to bloom with the Fostex drivers.

I'm simply going to conclude the SF speaker  /SDS4 amp combination is not a good one.

It will be interesting to hear from others with the same board with different difficult to drive speakers.

This is likely  a one of a kind situation or possibly the SDS4 doesn't play into difficult loads as well as Tom initially thought.

I guess I'll have to get the monitor speakers out now as my curiosity is up. The monitors have a
nominal 6 ohm impedence so they should split the difference nicely.

Kevin

Unless I missed something, you're still using the stock power supply, right? I think you need some real juice for those speakers. Hopefully the Connex will help. The difference in tonality though with your tube amp is a gap that probably can't be bridged, but as you said that should be expected given the near $4500 cost difference and differing amp topology. I think the top end improvement w/ the high efficiency is a clue. What's their impedance?

[Bemopti123]

Sonus Faber=one of the kings of low efficiency speakers, lovely sound but you need an elephant of a SS amp to run it well....Tubed PP/Sonic Frontiers, like the Power 2 I had, might produce something like 110 watts of PP power, much more powerful than the PA-7 200 watts/Nakamichi I had prior to the Power 2. 

The ClassD audio amp board design produces watts but not the more high current type that things like the Sonus Faber demands. 

I say try something like a regular, Class A/AB amp with large PS, like McCormack or if digital H2O...you will see a large difference in sound. 

Have we been struck by the digital hollow watts syndrome? 

[wushuliu]

Sonus Faber=one of the kings of low efficiency speakers, lovely sound but you need an elephant of a SS amp to run it well....Tubed PP/Sonic Frontiers, like the Power 2 I had, might produce something like 110 watts of PP power, much more powerful than the PA-7 200 watts/Nakamichi I had prior to the Power 2. 

The ClassD audio amp board design produces watts but not the more high current type that things like the Sonus Faber demands. 

I say try something like a regular, Class A/AB amp with large PS, like McCormack or if digital H2O...you will see a large difference in sound. 

Have we been struck by the digital hollow watts syndrome?

From all the feedback I've read on the CDA/SDS amps, the conclusion I come to is the true value lies in the amp boards, not the power supply. The stock PS is good enough for the majority of folks mind you, but when it comes to really getting the most out of them that's where you start - it's just as important as in any other amp design. I think that has been confirmed by some knowledgeable folks in different threads in regards to these amps. It's just that you can get away with less for the average user.