Digital Amps vs Solid State Amps

"first, 'd' doesn't stand for 'digital'....it was the next letter in order to be used."

Are there class C amps?

I've compared a W4S amp and integrated to a couple of Pass class A designs and would agree that it comes down to personal preference. In my case I preferred W4S, but not by a wide margin.

Are there class C amps?

Yes, but they are not used in audio:

http://en.wikipedia.org/wiki/Electronic_amplifier#Class_C

Also, re "Digital Amps vs Solid State Amps," I'm not sure it's clear that "solid state" has nothing to do with amplifier class. It means that the amp uses transistors, as opposed to tubes. I don't think there are any Class D amps that are NOT solid state.

Also, a true "digital amp," such as the TacT's, has a digital input and a signal path that is entirely digital until d/a conversion is performed, at a point in the signal path that is very close to the amp's output. See http://www.tactlab.com/Products/MS2150XDM/FutureofAudio.html

Regards,
-- Al

Thanks, Al, I was just getting back to this and you'd covered it.

I think the first 'd' amps were years ago, before SS. So they must have been tube.

This is just a comment related to your current speakers, the 3.6s need alot of power and Class A power cost alot of $$$. From a pure finacial point of view, I think you will find it easier to find good sounding Class D at a lower price, but not sure I would not go A/B if I wasn't going to use Class A SS.