2. amps-preamps
  3. 189470-161121

Could Class D really be that good?

I've heard statements praising modern class D amplifiers all the time but was sort of hesitant to try. Lately, one particular model caught my eye, the Fosi V3, which costs sub $100 but is praised for having refined sound like class A/B. To fulfill my curiosity, I quickly ordered one and tried it with my Burchardt S400II and Wharfedale Linton speakers. Basically, this is a neutral sounding amp but, to my surprise, the sound is clean, open, airy, with full mids, wide soundstage, good imaging/separation, with nearly null traces of the edginess, dryness, or lean sound that traditional class D amplifiers have. The background is just as quiet as my current systems. The core is the TPA 3255 chip from TI and comes with a 32v, 5A power block, which is supposed to deliver approximately 65 watts per channel (into 8 ohms). It drives the S400II/Linton without any hesitation, as well as my 130-watt-per-channel high-current Parasound A23. Very impressive.

Measurement is not everything. However, according to the lab test results, when operated under 10-60 watts, the distortion level (THD) is below 0.003%, better than a lot of high-end (price) gears. I am going to build around it for my fourth system with upgraded op-amp and LPS. I believe it will outperform my current mid-end (price) amplifiers.

I know, I know, quite a few Audiogoners' systems are above $100k, and mentioning this kind of little giant that costs a fraction could be rather embarrassing. But I thought this is just like gold digging with a lot of surprises and fun. Don't you think?

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thecarpathian's avatar
thecarpathian
4,363 posts
 

@pindac ,

That's terrific!

Thank you for taking the time to search this up.

pindac's avatar
pindac
2,864 posts
 

The first time I read the asr Link is today in the last few minutes, I am glad my description of listening to this Amp design, supplied Signal from a Vinyl Source and Soulution Pre Amp', seemingly suggests the measured performance is able to produce sound that is quite attractive to some individuals preferences for a produced sound.

Some of the Neurochrome owners I know, and have been instrumental in their becoming users of Neurochrome designs are now, seriously investigating (actually building) up to date designs from Purifi, which is the evolved design from Bruno Putzey. 

edavis's avatar
edavis
20 posts
 

I had a Krell FPB 200:amp, with a Pass Labs Aleph P preamp driving a pair of Martin Logan ReQuest speakers, and a dealer talked me into trying a Peachtree Nova 220:se to replace my Krell am and Pass preamp. I was totally amazed at the sound quality and performance of the Peachtree integrated amp, which was a class d amp. I let my ears make the decision……I sold the Krell amp, and Pass Aleph P preamp and used the Peachtree from then on out. The Krell and Pass systems were both Stereophile grade A systems.

jayctoy's avatar
jayctoy
4,040 posts
 

Class D got better.

desktopguy
367 posts
 

My nearfield desktop audio system is very crowded and had no space for an A/B or A amp of any kind when I switched to passive monitors ~6 years ago. Thus I was pushed into the alien (to me) world of class D amps. I did a ton of research, looking in particular for any class D amps described even occasionally as "musical" and pleasing to the ear. All that research led me to a gently used ICEPower design, the Wyred 4 Sound ST-500, which I sited standing on one side on my desk (w/the mfr’s OK). That cool running amp immediately worked well for me. It sounded great, had none of the obnoxious brightness and thin harmonics some ascribe to class Ds. Until a month ago I wasn’t tempted to change.

I never really stopped following class D, and had become curious about NCore modules used by various amp makers. The one other (to me, somewhat affordable) class D brand I read positive things about is Bel Canto. I looked for their stereo NCore amp, but instead found a cherry pair of 600M monos. After installing them  IMS, I can verify that they, too, sound quite musical. They have somewhat more resolution and better soundstaging than the ST-500, which is nice to have.

I got pushed into class D by space considerations but must say I’m quite impressed with the sound of the 3 examples I’ve used in my system. I've had 4 pairs of studio monitors here with these amps (ATCs, KEFs, Aerial Acoustics, Harbeths) and all worked extremely well with these amps.

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