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?


A simple upgrade is to order the Fosi with the 48 volt power brick. Go to ASR to read the recent test report.

I have been using the  LSA Warp 1 Class D in my system since last September. The Warp 1 also uses the Texas Instruments TPA3255 “Purepath” Class D circuit. I replaced my second Willsenton R8 with the LSA Warp 1. I was using the Warp 1 to drive a completely refurbished Audible Illusions Modulus 3 A pre-amp into my Tekton Lore Be speakers. That sounded very good to my ears. I recently purchased the Eversolo DMP-A8 pre-amp streamer and for curiosity's sake, removed my Modulus pre from the chain. I moved to balanced interconnects between the DMP-A8 and the Warp 1. WOW...This combination is so quiet. It improved the definition, soundstage, and instrument position in the music without being harsh or fatiguing. I like it better than with the Audible Illusions tubes in my system.  I now know the DMP-A8 has a true analog circuit for my vintage Pioneer 707 turntable. I don't have much to compare it too, but it is truly a step up from the AI Modulus I was using. I am totally impressed with the LSA Warp 1 / Eversolo DMP-A8 combination. Here is a link which describes the Warp 1 circuitry in detail. Of course, your milage my vary.


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