Class D is just Dandy!

,l with In my experiences with good quality class D ampsThey just faithfully amplify the inputted signaout adding or subtracting anything. They’re like the audio amp ideal of a "straight wire with gain".

Sorry they don’t look the same, just look at any 1-10khz test shot of input v output wave form.
And then without their output filter, the input wave form will be unrecognizable from the output, because of the HF garbage, and melt your tweeters silently in a nano second.

It’s like a customers preamp I had to work on, the owner said it sounded little bit hard, a quick look on the scope showed the output wave form looked just like the input wave form, all looked fine?.

Then I looked with the scope in the center of the preamps circuit, and found the wave form unrecognizable from the input with the amount of hf garbage on it.
That center amplification stage was oscillating its brains out!!! And all they (manufacturer) did was to filter it out at the end stage, instead of fixing the source of the problem.

I compensated the center stage so it didn’t oscillate anymore and removed the end stage output filter, and the customer was happy.

But you can’t do this with Class-D, so the only thing to do is to raise the sw noise in it even higher (1.5mhz) so then the output filter then can do it’s job fully without any phase effects down into the audible frequencies.
Then a Class-D’s input wave form will be much closer to matching it’s output wave form.  "straight wire with gain"


Cheers George

There is no such thing as straight wire with gain.  Every single inch of wire sounds different from every other kind of wire and even the directionality of the wire makes an audible difference.  Every single thing inside a power amp (class A, B, C, D or whatever) changes the sound.  This is why every class D amp sounds different from every other one.  They don't all have no sound or the same sound.  I did 14 mods to the IceEdge modules to make them sound more dynamic, musical, extended and transparent.  There is no end to infinity.  We have not reached any sort of final class D sound orgasm..  If class D sounded perfect with mosfets, then why would we be looking at GaNs?  Nothing is perfect on this plane....all is perfect in spirit......all is suppose to be this way....perfect in its imperfection.....and always we strive for more perfection.....hey, its fun!

Erik, three years later, and still going strong, excellent thread.  Class D is the bomb, and your thread would seem to amplify that message.  I purchased a D.A.C. older amp for my first try at Class D, A/Bs left something wanting.  My Signature Technology is a very nice tube amp, the cymbals never sounded right.  The DAC4800a was my first thousand dollar amp.  It has been a delight ever since, so much so, I purchased a used Maraschino 60 volt model.  Absolutely delighted with each.  The 4800a uses a toroidal transformer, the Maraschino a linear power supply.  Currently saving my money for another 60v Maraschino, will have to be new as these amps seldom come up in the used market.  In another class compared to my Acurus or MTX Soundcraftsman.  Use any adjective in the audio lexicon and these fit and fulfill those descriptors.  I would really like to hear a review about the DAC amps from you.  With respect, Jerry.