Please review the site Rules, Terms of Service, and Privacy Policy at your convenience. Rules, TOS, Privacy
Get familiar with the reaction system: Introducing the Reaction System

ClassDaudio amp project

I decided to start this new thread to share pictures and details of my new amp project.  Unlike most of my projects this one will NOT be housed in a hardwood, 4 sided case, with an aluminum top and bottom.  Our IT Manager at work called me a few weeks ago and asked if I wanted an old UPS unit that he was upgrading.  Hating to see anything with potentially useful parts go to the scrap heap I said "Yes!"  Nothing inside except the muffin fan was worth keeping... but the case!  A perfect case for an audio project!!!!  Of course it'll need some modification, specifically a new rear panel.  I'll snap some pictures of it.  

The model of amp board I purchased was the CDA-250:

http://www.classdaudio.com/cda-amplifier-modules/cda-250-power-amplifier-module/

I already have a 400VA 35-0-35 VAC toroid transformer and a small power supply board (rectifier and cap banks).
jr@macD1PP1NkennykS7910Gowa4thtry
«13

Comments

  • If I'm not mistaken, all the ClassDaudio boards are based on IRS2092. It can produce great sound, my HT amp is built from five L15D-Pro modules that you can find very cheap on eBay, especially if you don't mind soldering them yourself. The L15D is basically a copy of the IRS2092 eval board from International Rectifier, I'd imagine the CDA-250 is not much different. You won't be disappointed.
    kennyk
    What?
  •    Why this vs the B&O Ice, cheap t-amps, or some of Hypex's offerings?
  • DIY for the sake of DIY :)
    kennyk
    I have a signature.
  • That's a good question KB.  I've already built a ClassDaudio amp using two bridged SDS amp boards.  That amp can do 500W x 2 into 8 ohms and much more into 4 ohms.  The ClassDaudio boards sound awesome to me.  This CDA-250 board is the same one Pete Schumacher used (although he used 2 bridged) in his PCeceiver project he demo'd in Iowa a number of years ago.  I have never heard the Ice or Hypex boards, I have read that they are great too.  But every other "cheap" amp module I've heard, like the Sure Electronics and Yuan-Jing stuff, has not sounded very good to me at all.  Some of it sounded flat out bad.
    Kornbreadkennyk
  • Here are some pictures of the case.









  • Here is one possible layout.  I will play around a bit to find the best layout:



    D1PP1N4thtry
  • What's the difference between the CDA and the SDS boards?
     John H, thanks to JP I did get that email
  • It is my understanding that they share the same core circuit topology and IRS devices. The SDS boards have:  balanced inputs, larger finned heat sinks, and molex connectors which allow off board gain controls.

    Since I run a single ended signal chain, I am going to sister a larger finned heat sink to the existing one, and I don't need external gain pots, the CDA seemed appropriate.

    There maybe other differences I am not aware of besides the $100. Lol
    .
  • edited December 2017
    PWRRYD said:
    That's a good question KB.  I've already built a ClassDaudio amp using two bridged SDS amp boards.  That amp can do 500W x 2 into 8 ohms and much more into 4 ohms.  The ClassDaudio boards sound awesome to me.  This CDA-250 board is the same one Pete Schumacher used (although he used 2 bridged) in his PCeceiver project he demo'd in Iowa a number of years ago.  I have never heard the Ice or Hypex boards, I have read that they are great too.  But every other "cheap" amp module I've heard, like the Sure Electronics and Yuan-Jing stuff, has not sounded very good to me at all.  Some of it sounded flat out bad.
        Thanks, that's the answer I was looking for. 

       I've read the irs2092 can sound lean on the bottom and a little bare otherwise.  Also heard that of the Hypex ucd and n-core offerings but with a full bottom end.  I don't know if there's as much a difference as some make or if it's a fly shit in pepper thing.  They all spec fantastic, the n-core exceptional.

       I'm in the market for an affordable drive anything amp that sounds good, (full but controlled bottom and smooth but not subdued mid/treble, I hate glaring treble) where I can close my eyes and reach out and touch the performers.   

       What have you tried, or heard, and your take on them, good or bad.

       Is it possible to mate something like the irs2092/ICE/Hypex with something like the tube pre your working on, and have the best of both worlds?       
  • edited December 2017
    I love my Crown XLS Drivecores, for another recommendation.
  • How low an impedance can this handle, bridged and non-bridged?
    ............. could you hum a few bars.
  • If that was directed towards me- Bridged at 4 ohms, and stereo at 2 ohms.
  • Do the drivecores have dsp built in like the inukes? Im going to have to pick up something else i was using a small amp and my minidsp but stopped using it. Prefer an all in one solution. 
  • The XTi series does have DSP. The XLS have HP/LP filters, and that's about it. Be forewarned though- I hear the fans on the XTi are a lot louder than on the XLS.
  • edited December 2017
    Wolf please start your own thread about your commercially purchased pro amp.  This thread is about my DIY project.
  • Of course it is- no hijack intended.
  • Sorry to sidetrack your thread Craig. 
  • Guess I'll hijack my own thread a little...  I'll be getting back on this class D project soon.  I've just been busy finishing up that tube pre-amp project, helping my son build a Pine Wood Derby car, and building some snow people.






    D1PP1Nkennykjr@macS7910Gowa4thtry
  •  I built a 2092 amp with some L15 boards and that buyout PS.  Sounds pretty great to me, and lots better than any of the dinky 3116 or 2022 amps. 
  • Your case has a nice added benefit of a built in divider for some ps shielding.

    I see you said you will add another heat sink, do you plan to expose that on the case or keep it inside?
Sign In or Register to comment.