Who tried Class D only to return to S/S or Tube

I’m  a little puzzled by all this "switching" talk.  My class D amp has 60kHz bandwidth while tweeters are almost completely quiet with my ear next to them (200W amp).   I’ve read the same in many reviews of different class D amps.  It was much worse with class AB amp in the same setup.   Highs in my amp are very clean while midrange is simply wonderful.   As for SMPS being noisy, nothing can be further from the truth.  New zero current/zero voltage switching SMPS are extremely quiet and that’s why Jeff Rowland uses them not only in class AB amps but also in preamps purely for their low noise (efficiency is unimportant in preamps).  Just to show an example:  Benchmark reduced noise floor in their latest DAC by 10dB using SMPS instead of Linear PS used in previous model of the same DAC.  It is because Linear PS is not linear at all.  It is simply unregulated noisy switcher that switches at 120Hz at max voltage producing not only hard to filter 120Hz but whole bunch of high frequency harmonics - since current is taken from the mains in huge narrow spikes.  Power supply is line and load unregulated and requires huge amount of capacitors to keep voltage steady.  These high inductance capacitors are in series with the output (circuit closes thru them).  Adding parallel non inductive caps might help but it will also create (with inductance of electrolytic caps) a parallel resonance circuit that will ring.   That’s why class D amps with SMPS are praised in  many reviews for keeping composure under heavy peaks (orchestra’s forte).  Lets forget about "switching" - speakers are unable to play 400kHz while we are unable to hear it at all.  It is imagined problem by "experts" that have absolutely no clue trying to find something wrong. Class D are linear amps where duty cycle, instead of voltage, is used as adjusted quantity.  

2nd generation is already here. Ableteck, Pascal and Hypex are all making 2nd generation class d amps that are competitive with nearly anything ss or tube based at less than ridiculous prices.

There is no issue with the switching frequency nor the filtering in these modules. None of these produce any audible distortion products at the tweeter. I have heard all three. They are all excellent and have been well reviewed.