Class D Technology

Hi Guido,

     Very good summary of the evolution of class D over the last few decades.  I've become familiar with your thorough knowledge of most things class D over the last few years and I'll take your word for it that early class D amps did suffer from some of the ills that the op and george have discussed..  Luckily, I avoided the early disappointments by not using class D until the last 2-3 yrs.  I've experienced no high frequency harshness, brightness or any other negative treble qualities and thought they were referring  to more recent class D amps.

     I'm not a fan of  bright sounding amps of any type and, if any of the class D amps I currently use shared any of those qualities, I would not have kept them and definitely would not be recommending them to anyone.

 Guido said::     

"Please note that exactly like proclaiming that all class D amplifiers are inherently flawed constitutes a logical fallacy, so would be the assertion of the opposite... Reality is, that with all topologies, some amps will meet our particular taste in music reproduction, some will miss by a country mile, and some will be somewhere in between."

     I agree with your summation completely.I think you're correct, the reason I enjoy my current D-Sonic M3-600M amps so much is because they match my taste in musical reproduction so well:

Very good bass response that is deep, solid but also nuanced when required.

Very low noise floor that enables details to be heard.

Powerful for good dynamics and a relaxed and effortless quality on all content that allows music to sound very natural and life-like.

Dense, solid and stable imaging that allows for the illusion of a 3-D sound stage both laterally and front to back.

A smooth mid-range and treble that also manages to be highly detailed.

A generally accurate and neutral presentation that is capable of conveying warmth when it's contained in the music and captured on the recording.

     This is a summary of what I hear when I listen to my class D amps.  It is a combination that suits my tastes well but I realize may not suit others tastes and I realize not everyone will even .hear the same qualities from these amps in their system and room.  as I do in mine, it's to be expected.

Tim       

guidocorona

Thank you for your post dated 12/11/16.  After the many aimless ramblings about Class D, your post is a breath of fresh air.

bcgator and mapman I am with you guys all the way. I had the GT200 mono block tube amps from Tube Research Labs. They were by far the best tube amps I have ever heard. Does that make me an authority? Absolutely not. But when I replaced them with H2O 250 SE mono blocks my world was turned up side down. Were the 250s as warm in the mids? No! But guess what.I used a tube pre-amp (the TRL Dude) the Ayon Skylla 2 DAC and I was 90% there in the mids. What I did NOT have was distortions (even order nor odd order) that was obviously missing since replacing the tube amps. I have the Sound Lab A3 PX speakers and as you say " full range" with a vengeance. Unfortunately components add their own color. That is the nature of the beast. So system matching is always the challenge. Just bringing the Sound Labs 4 inches closer to each other dialed the sound right in. I hear the arguments and look at the measurements  and guess what the sound contradicts those arguments and measurements. Not one of my audiophile friends has not been floored with the sound. They too have heard the class A tube monos and said these thing eats them for lunch. I think it was you Mapman that said you changed a cable. There you go, system matching. If you are ever in Columbus, Ohio stop in for a listen.

My advice for anyone on the fence is do your homework, listen and decide for yourself.   Only then will you know.

   I'm no scientist but I understand the difference between theoretical noise and actual verifiable noise and that, empirically, only the actual noise can actually be heard. by us humans.  Noise needs to be heard to exist.  

Class D amps are nearly immune to any noise they (or their SMPS) might make. The switching occurs at the output of the amp to which speaker cables are attached, which might make a suitable antenna.

Its the other gear in the system that is really the concern (not to mention pacemakers and the like in the area)- they might pick up the radiated RF noise and might react poorly to it.

However, neither of these are really issues with any competently designed amp or power supply, and while I get the concern, its mostly a red herring. You would never be able to ship an amplifier (or power supply) out of the country if it made any appreciable noise!

So I don't think this is anything to be worried about.