[rajesh]

Brian Bell chipamp.com LM3886 gainclone or Class D Audio CDA-224...?

Some of you have experience with both amps, so I'd really like your input.

After building the class D CDA254, since I was not impressed by it rendition of LF content, I went ahead and built a Myref amp which is modded by linuxguru of DIY audio fame which is based on LM 3886. I've posted about the build http://www.hifivision.com/diy/11495-group-buy-mauro-penasa-myref-rev-c-kit-3.html#post176384 and http://www.hifivision.com/diy/11495-group-buy-mauro-penasa-myref-rev-c-kit-4.html#post183538
It is a fantastic sounding equipment and cost me about 2k INR (about 45 USD)

I have since sold it to one of the forum members who wanted to do some experiments and wanted to have one badly and no more kits were available.

[firedog]

Tom finally got back to me with this reply:

The SDS-450 is made to run very tough loads... even below 2 ohms. It puts out 150W RMS per channel into 8 ohms, 300W RMS per channel into 4 ohms, and 600W RMS per channel into 2 ohms. It's a very powerful amp. It looks just like, and is the same size as other SDS amps. It has the same sonic qualities as our other amps meaning it is one of the finest sounding amplifiers available today. You can read some customer reviews here, and the first is in regards to this amp... http://classdaudio.com/index.php/testimonial

We have one other amp called the SDS-470 which does put out 250W RMS into 8 ohms and 500W RMS per channel into 4 ohms. It's also made to run tough loads. The cost is $590.00 plus shipping cost. Shipping here in the USA is about $25.00 to $35.00. we use all top of the line components and my tech is really a perfectionist and does a beautiful job assembling them.

This sounds like an incredible bargain to me...definitely cheap and cheerful. I think I may give it a try.

[corndog71]

That's not bad.  I paid around $600 total for my SDS-258.

[wgscott]

Tom finally got back to me with this reply:

This sounds like an incredible bargain to me...definitely cheap and cheerful. I think I may give it a try.

I realize I never got back to you, but with the caveat that I am still quite new to this hobby, I have been extremely impressed with the amps.  One of my amp boards had a problem, and Tom immediately fixed or replaced it (I am not sure which) and got it right back to me, so I can also endorse the customer service. 

I am currently passively vertical bi-amping with two SDS 254s, with an eye toward making it active in the not-too-distant future.

[firedog]

WGscott-

No problem. You post enough at the various forums that I got the picture.

BTW, I ordered a built amp from Tom yesterday. New model, SDS-470. 250W X 2 @8 ohms, double output @ 4 Ohms. In silver desktop style case. One 2 channel amp board inside. Price, $590, assembled, before shipping. Discount code: "ACircle" knocked another $30 (5%) off the price, so it was $560, net.

Tom gave me the initial quote, and then I asked if I could shorten the process by calling and asking a few questions. He said he's hard to get a hold of and he'd rather call me. Called a few hours later. Answered all my questions. Great customer service. I ordered immediately.

I see this as a pretty low risk proposition. Basically it seems Tom is now offering complete models in a case, built to order (mine is 220V), for about $200 - $250 above the price of his corresponding kits. It would cost me about that to buy the case and additional parts where I live. Tom told me his tech who builds them is a perfectionist and does an outstanding job, so the build will also be better than what an inexperienced guy like me could do, and I will know that the build "works".

The directly competing models on the market (almost all use ICE modules) with similar output cost from $1500 to $3000 - almost 3-6 times as much. Nightshade audio also makes amps based on Toms boards (I think Nightshade uses their own proprietary PS), but even his prices are a few hundred more than Tom's, even with a basic case. ($850 for a basic CDA model with 125W X 2 into 8ohms,  250 X 2 into 4. Nightshade does offer lots of case options/colors though).

All reports/reviews seem to point to the ClassD being competitive in terms of SQ to the class d competition. Obviously personal taste makes a difference in how you perceive the SQ of the result. I doubt I will be disappointed in the sound, as I've heard a few ClassD amps (Nuforce, Bel Canto) and liked them.

I guess I could decide that the unit doesn't look nice enough. But if that really bugs me (which I doubt, the case seems to have a basic "utilitarian", but not ugly look) I can always order a custom faceplate or build a wood enclosure and improve the looks for a modest sum.

Anyway, Tom told me that it would take about a week to be ready. International shipping and customs clearance will take about another week. So in about 2 weeks I should be able to report back with first impressions. Also pictures, if I can get enough light in the room to get some clear ones with my pocket camera.

[soundnoob]

Why are people still buying the kits? Doesn't it make more sens to buy a SMPS from Connex or something?

[walkern]

The SMPS from Connex takes quite a while to get shipped to the US, and costs more than the power supply that Tom offers with the kits.  I've tried both, and I'll be darned if I can hear any difference between the two different power supplies with the SDS 254 amp module.

[wgscott]

WGscott-

No problem. You post enough at the various forums ...

Only this and CA.  Anything else and it is an impostor.

I can always order a custom faceplate or build a wood enclosure and improve the looks for a modest sum.

That's what I did.  My front plate came to about $150.  I spent about $300 on the case, total.  Although it looks ok, and matches my Nova, my assembly job is definitely amateur hour. Having it done right is definitely cost-effective, and, as you say, you can always swap in a different face plate.  I used http://www.frontpanelexpress.com and I can give you the Class D Audio engraving logo image thing that took me forever to make, if you are interested.

[earflappin]

I have two SDS-224 amps I use in a bi-amped active crossover set-up.  Tom (of Class D Audio) has told me that some of his customers have reported hearing sonic differences with various PSU configurations and others not.  Obviously, these type of anecdotal comments depend on the system and the listener in terms of how discerning both are or not.  I currently use a discrete PSU consisting of: Antek xfer > Valab 12ns ultra fast rectifier > 3 15,000 uf Jensen 4 pole caps > SDS-224 audio circuit. 

I was wondering if anyone could weigh in on their experience in terms of what/if any sonic improvements they have heard by optimizing their PSU's.  Certainly, the SDS amps don't need a regulated PSU, but I've been toying around with trying one of Paul Hynes' series regulators in my PSU.  Thanks for any information you can share.

[wushuliu]

The SMPS from Connex takes quite a while to get shipped to the US, and costs more than the power supply that Tom offers with the kits.  I've tried both, and I'll be darned if I can hear any difference between the two different power supplies with the SDS 254 amp module.

The fact that they sound the same to you is still good news for the Connex! as I'm sure a lot of folk are skittish about the smps sound quality. Other big plusses are ease of use and weight for newbies: fuse is built-in so no need to worry about wiring that, much less wiring needed period than the stock PS, (therefore) decreased high voltage risk, and the fact that the Connex weighs absolutely nothing and takes up a small amount of space - an equivalent toroid is very heavy and along with the capacitor/rectifier board, limits enclosure options.

Ordering from Connex does take some patience though. Ack.

[MDI]

Hi All,
Just for understand, why my first post is stopped? maybe it is a publicity...I think it is a information for diy.

Regards

[Letitroll98]

Hi All,
Just for understand, why my first post is stopped? maybe it is a publicity...I think it is a information for diy.

Regards

Welcome aboard MDI.  It has nothing to do with you, we had (have) a big problem with spammers on the site, so it's a security measure to verify that you're a real person, not a computer.  When you get to three posts you'll be able to post unrestricted.  Thanks for your patience.

[zoula]

Hi,

I'm a long time reader of this tread and I want to share with you what I did with a SDS-254. 

I did an integrated amp with a preamp kit from Dantimax.  http://electronics.dantimax.dk/Kits/index.html

I now have an amp with 6 inputs a digital volume control with a remote and a nice blue display!!!!  The amplifier will be build in a nice wood case.  I have some nice wallnut burl that I could use.... 

But so far so good.  The amp sound very good. 

I will post the photos when the enclosure will be finish,  probably not before mid September...

Thank you all for the inspiration

Zoula

[Rclark]

 Considering the new SDS-470, and the fully built models, do high quality, hi-tech solutions like this mark the end of the kilodollar amp?

[HT cOz]

What is SDS 470?

[TrungT]

New model, SDS-470. 250W X 2 @8 ohms, double output @ 4 Ohms.
 
http://classdaudio.com/sds-470-and-power-supply.html

[srb]

New model, SDS-470. 250W X 2 @8 ohms, double output @ 4 Ohms.
 
http://classdaudio.com/sds-470-and-power-supply.html

Where do you find the specs?  When I go to the page you linked it only shows the details "SDS-470 amplifier with large power supply ".  The complete SDS-470 amplifier page also has no details other than "Custom made SDS-470 in Silver Desktop Case wired for 50 cycles, 220V".
 
The SDS-480 kit page reveals that it is an "SDS kit including two SDS-224 Amplifiers, transformer, and large power supply".
 
I also checked the Manuals page, but there are only the original manuals for the original amps before there were CDA or SDS model designations.
 
It's good that the amplifiers work well and the majority of builders are satisified, but the information available on the website is still to this day as confusing and sketchy as ever and hasn't yet given me the confidence to take the plunge.  Maybe there will be details available soon for the new assembled amplifier offerings.
 
Steve
 
 

[TrungT]

Class D Audio website over due for an update. 
There are few AC members contacted Tom about the SDS-470 and that how I got the info. from.

[corndog71]

Where do you find the specs?  When I go to the page you linked it only shows the details "SDS-470 amplifier with large power supply ".  The complete SDS-470 amplifier page also has no details other than "Custom made SDS-470 in Silver Desktop Case wired for 50 cycles, 220V".
 
The SDS-480 kit page reveals that it is an "SDS kit including two SDS-224 Amplifiers, transformer, and large power supply".
 
I also checked the Manuals page, but there are only the original manuals for the original amps before there were CDA or SDS model designations.
 
It's good that the amplifiers work well and the majority of builders are satisified, but the information available on the website is still to this day as confusing and sketchy as ever and hasn't yet given me the confidence to take the plunge.  Maybe there will be details available soon for the new assembled amplifier offerings.
 
Steve

I wouldn't hold your breath.  Tom seems like a funny guy.  He makes these kits available for the DIY crowd.  And most of DIY types that have taken the plunge have been satisfied.  And that seems good enough for him.  This thread seems to be all the free advertising he needs to keep selling kits.

[roymail]

New model, SDS-470. 250W X 2 @8 ohms, double output @ 4 Ohms.
 
http://classdaudio.com/sds-470-and-power-supply.html

What is the difference between this amp and the SDS-258?  Thanks!