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

Not sure what others have said...but I've really like the Peachtree 220 and Rotel 15 series  class D amps.  Those 2 are very musical...and no reason to go back to A/B amps unless the configuration of a specific piece is something that you like.  Personally...I found older Bel Canto and Channel Islands to be a bit cooler sounding...some folks might call them a little "clinical" I'd guess.

kuribo, it appears that we need some common language here.  Saying "technology is mature" is a polite way of saying "It hit dead end" - therefore don't expect major improvements and place your order today. There are many technologies still improving in exponential rate HDTV, Phones, Computers, DSP processing etc. that most likely will keep improving, but it doesn't mean they are inferior to such mature technologies like B&W analog TVs.  The fact that effect is achieved by switching instead of steady value doesn't mean it is worse.  Plasma HDTV operates on class D principle and to many people it looks more natural (colors, motion etc) than LCD/LED HDTV.  Modulator used in class D amps resembles Delta-Sigma A/D converters that already went thru many years of improvements (PWM is a byproduct of Delta-Sigma processing) and in my opinion will keep improving for a long time.  It is not even a question what class amps are the best, but rather how good is the amp I can afford.  Many class D amps offer a lot for the money.

tfats, I've never heard Channel Islands but I know they were based on Hypex modules and had great reviews.  Bel Canto used Icepower modules (that my are in my Rowland 102 as well). Hypex had dual supply (+/-) but only two output Mosfets switching (thru Zobel filter network) one end of the speaker (the other end at GND).  Icepowers used single voltage but four Mosfet output bridge switching speaker direction between + and GND.  Somebody mentioned sound difference between two families, Icepower being closer to tube amp while Hypex closer to very good SS amp.  I'm not sure if output configuration has something to do with it or it is just different signal processing (modulator).  Hypex configuration is more practical (output can be further bridged), but I'm happy with Icepower.  It sounded different with different speaker cables - a little thin and colder with older AQ cable and fuller/warmer with Acoustic Zen Satori.  Lower midrange got stronger, cello sound fuller, male voices have depth (chestiness).  

I've briefly listened to class D amp's,  not my preference,  did the same with class a/be amp's,  btw, as it turns out,  my preference is class A solid state and tube equipment,  the heat has never bothered me that my amp has, to each their own,  I've always been a class A fan,  and likely will continue to enjoy for years to come. 

I think the main reason some folks dislike the "good" Class D of today who have actually tried it in their own systems is because they haven't let themselves adjust to hearing how a musical presentation sounds without audible distortion interfering. Yes, like it or not all that "creamy warmth" people talk about IS distortion that is not likely found on the original source material.

If there was a way to plug in a speaker or headphone directly into the CD Media itself with nothing else in the chain you will most likely arrive at the same sound today's modern Class D is capable of given an equally transparent Preamp,cabling and speaker. As an example, the noise floor on the Hypex modules lies almost as low as many of todays SOA D/A converters and way below the majority of PreAmps on the market. Going D/A direct or having a very good $$$ Pre is pretty much a requirement if you don't wish to hear those devices influence at the output.

I used to own some very popular Class A & A/B amps in the past and then one day decided to try Class D despite hearing all the negative impressions from folks who are heavily invested in tubes & classic Class A/A/AB amps. I will admit that it took me a while to get my mind and ears around what I was hearing. The presentation was VERY different with a modern Class D design (I have used Hypex NC400 & NC1200 exclusively). The stripped down and crystal clear output via the Class D amps can indeed be too much change for many people to bare.

The truth is, once you get past this sonic change in presentation and begin to hear your music thru a much cleaner lens it then opens the door to adding your Salt/Pepper seasoning in much smaller doses to suite your final taste.

In most cases this Salt and Pepper can be introduced via cabling & isolation tweaks instead of via a sledge hammer by way of using inherently "warm" components that add too much seasoning to the point of being so far from the sound of the original media that its not even funny. This is especially true when you consider the combined total of seasoning added by component, cabling, tweaks, speakers and what ever else you can imagine.

Personally I like having a totally neutral set of main components that remain true to the source and then add my flavoring via cables and isolation as needed. Understandably folks like myself are the minority in this hobby and in the end as long as we all enjoy what we are hearing it doesn't matter how you get there.