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?

lanx0003

Ralph,

It took you two days to reply and that is all you can come up with? You will say anything just to make me look bad so you can feel you are right.....wow! The two statements are not contradictory......I said "if it changes the measuremets". Again, never implied it did. You are just making something up to make me look bad, so that people might dismiss the fact that you stated something untrue. You are lying.....plain and simple. You cannot measure the distortion in high end used passive components......that is a lie.....and you know it. You have never proved that you can....and no other designer (that I know of) has ever said this except you.

The only way you can prove you are correct is to show measurements. The only intelligent (non ego driven) response to this post would be that:.....your measurements....your quotes from others who have tried this and show their measurements. Any other reply would just be from your ego.....(defending your postiion...without proof). So is the statement you made true? If so, prove it. Othewise it is a lie.

Why would someone make up stuff and post it online? I try to state what I know about....that is directly experienced or relay info from others who directly experience stuff.

I wish you well, but stating something on a public forum that is not true and then defending the statement by trying to make someone look bad who points out your untruth (rather that prove your original statement).....does not help your reputation. Why would I trust anything else you say if you just make up stuff and post it?

Now you are saying 6N copper is a myth. Can you prove it? Is this a belief or a BE LIVE? Please show us the measurements. From what I read, the claims of 7N and 8N are made up, but 6N can be real.  All wire sounds different no matter what the amount of claimed Oxygen free level. A single piece of wire will sound different depending on the direction it is used.....even PCOCC wire. All above sonic statements tested with my ears....so it’s a BE LIVE. Belden make the Iconoclast insterconnect cables and those guys are VERY scientific.....however, they make three different versions....pitch copper, OFC and PCOCC. They go up in price accordingly. Every one who has reviewed them agrees that the PCOCC ones sound the most transparent. Everything makes a difference....my usual statement. And Everything is LOVE.....the statement of the Universe....every second. Enjoy.

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

I did try the 48-volt PSU, but the truth is, it doesn't deliver better sound than the 32-volt PSU at normal listening levels or even at 80-85 dB. Surprisingly, the 32-volt PSU offers cleaner sound, leading me to believe that it is the better and less noisy SMPS option. Moreover, in terms of power requirements, the 32-volt PSU proves to be more than sufficient for a small to medium-sized room.  The 48 volt psu also drives the amp unit noticeably warmer than the 32 volt which will potentially shorten the left span of the amplifier.  Not recommended.

I am with ricevs. As I do with many pieces and doing it for over 50 years, I finally got around to chassis damping my LSA GAN 350, including changing out the stock rubber feet. What I hear now vs stock, are cleaner, faster and more agile sounding transients, more air around the instruments, greater articulation with the "playing" of the instruments, and greater dynamic contrasts. The rear panel alone was very "alive and ringy", and now it is dead silent. The power cord, interconnect cables and speaker cables all have a quieter environment to contend with. Everything makes a difference in what I hear. Could care less if it is measurable. GANFETS, to my ears and in my system, are the most enjoyable class D I have heard, and in the last 18 months, I have heard many. My best, MrD.

+1 mr decibal

Recently, Steve Guttenberg compared several class D amps on his YouTube channel. worth listening to

I have both a Ric Shultz EVS 1200 and a LSA Voyager 350 Gan amp. Both are great amps, especially for <$3000. I've seen an occasional Voyager listed for under $2000