Oh how I wish Class D amps ...

Please see first schematic::http://users.ece.gatech.edu/mleach/ece4435/f01/ClassD2.pdf
L1 / C1 are how the switching frequency is removed.....and should induce a phase shift in the audio band. No?

Simon,
Want a good example of an Analogue computer?
Please see link:

http://en.wikipedia.org/wiki/Analytical_engine

Charles Babbage could never get it together long enough to build it, but within the last decade or so, Smithsonian built one to the original drawings, and it worked fine.
The machine would have been used to calculate log / trig tables for navigators and such.

Well ... I guess I am wrong for assuming, but I do assume that EVERYTHING is always subject to system synergy. Having said that, the Cirrus speakers are the single best tool I have ever seen for component and wire evaluation. They are an open window, and PERFECTLY show every slightest change made upstream. So I am fortunate to have a system that does allow for very good evaluation.

I have no adgenda to bash digital amps, just a desire to see them improve.

I think we all might have a bit of "that" same centricity that our speakers (or other gear) is neutral and that it shows the distractions of all other gear, but I tend to think that is not always so.

I think most might offer that "switching" amps have exceptional highs (in the better ones) and if your speakers are not letting you hear that, then what does that tell us?

In the end, it is finding the components that sum to our preferences.

The single characteristic that most impresses me about my digital amplifier (Tact) is the absence of noise-white, pink, or mechanical-it is simply absent. The result is that one can hear much more low level detail and much less compression than with any conventional amplifier I have used. Don't get me wrong, I have owned and loved well designed tube amplifiers (ARC, Music Reference, VTL), but they do make noise and compress the signal. I submit that many of us have simply got accustomed to these distortions, as previously we had got accustomed to tape hiss and grove rush. Because two channel sound is not the natural way we hear, the brain has to decide if a simulation we have created is "correct", meaning the usual distortions

All I know is that I had Bryston 7B-st amps, traded them for Rowland 201's and they didn't cut it. Now I'm back to big beef -- Cary MB500's. Speakers were Maggie 3.6's and Aerial 9's.

The Rowlands lacked oomph (in my system -- YMMV)

Rich