Class D audio vs James Romeyn

bakalovb,

     My first class D amp was a classDaudio SDS-440-CS stereo unit I bought about 3 yrs ago.  I was very impressed with this unit that replaced a class A/B Aragon 4004 MKII.  It's very powerful (220 and 440 watts @ 8 and 4 ohms), is very affordable ($630), has an extremely low noise floor, great bass response,  excellent dynamics, has a very neutral character and has a very detailed but smooth mid-range/treble that is never harsh or bright.  This amp is also 1/3rd the size, weight and price of my former amp while never getting warmer than luke-warm no matter how hard it's driven.  Highly recommended.

     I believe the James Romeyn class D amps you mention is a kit built stereo amp based on the Hypex 400 power modules and switching power supplies.  James builds these kits in a custom case for about $1,500.  He also offers the same amps in mono-block form for a higher price.

     I have not heard this amp but, from what I've heard and read about them, the Hypex 400 kit amps are also excellent performers that have similar qualities as those I attributed to the classDaudio amp I own.

     There is another class D stereo amp that I know is very good in your price range; the D-Sonic M3-800S for $1,475. 

        http://www.d-sonic.net/products/stereo-amplifiers/

     The D-Sonic uses a different power module from a Scandinavian company (Anaview/Abletec) that is based on phase modulation while the 2 you are considering use pulse width modulation (PWM).  

     I own the mono-block version of this amp, M3-600-M, and can tell you this is the best amplification  I've ever used in my system.  They have the same attributes as my classDaudio amp but with more power, even better dynamics with an even smoother and sweeter mid-range and treble.  D-Sonic offers  in-home trial periods , too. 

    I'm not a dealer, just a fan of good class D amps 


Tim   

      

Thanks to everyone for the very useful information. There is one more class D company that also offers in home trial- Digital Amplifier Company? Anyone familiar with them? 

Don't forget the NAD M22!

 emb: D class will never be as good as A or a well done AB or a great tube amp.

I understand your point of view. I use switching amplifiers yet I listen with tube amplifiers which is why I respond to statements like yours from time to time.

I grew up with vacuum tube amplification, suffered through the infancy of early solid state and realized my beloved Ayre V-1xe was aging out after years of continuos use.  I purchaced the inexpensive the PS Audio HCA-2 before its review purely as a stopgap but became enamored by its virtues which tube or linear solid state simply can't touch. I've had a switcher in the house ever since. 

Yes, most switching amplifiers have a fundamentaly different presentation. In my case a pair of originally offered Hypex nCore 400s fastened to a hunk of 6/4 Maple that drive my studio monitors with amazing clarity, transparency, and seemingly unaffected by gain (within reason). As you say it would take a "great" as in $$$ to approach this type of presentation. What my $1248. plus shipping gets me is a plate glass view into my small world of mixing.

Even though I prefer listening to my all tube analog system the Hypex design was a huge sonic leap in switching amplification which IMO has taken yet another huge step up. I just heard one of my home made files played through an Anthem pre/pro processor feeding a 200 watt ATI Class D driving some Joseph Audio floor standing speakers.

bakaolvb, read the Kalman Rubinson review in the March Stereophile. Morris Kessler's work speaks for itself. 

bakalovb I forgot to mention.

I'm essentially using what Romeyn builds sans the casework and includes a version of the Hypex switch mode power supply. The two channel 200 watt ATI AT522NC ($1895. w/seven year transferable warranty) uses a Kessler designed power supply which should be of interest.
 
I had never been in the room nor heard the system the ATI Class D amplifier was driving so I can't comment on the sonic differences betwee the standard nCore with a switch mode power supply to the ATI. On the other hand I would strongly suggest an audition of the ATI or trial period, if possible. The two channel ATI is only a few hundred dollars more than the current build DIY nCore 400 kit.

If you follow Class D amplifiers you'll soon learn a large portion of their performance relates directly to the AC power they're fed. I found the quality of the utilities voltage as well as the design of the dwellings wiring from the utilities main to the wall receptical made a very noticeable improvement in mt home. When I replaced my homes Romex with uninterupted dedicated 20amp 12 ga. metal clad BX my entire system benefited but the switching amplifiers are what really benefited. The ATI's power supply design may ameliorate the usuall Class D AC issues.