Class "D" amp? I do not have a clue. Do you?

"The ASP1000 module is worst in this respect being what....about 1/2 db down at 20khz w/4 ohm load?"

Magfan - you're right (just checked datasheet graphs) but 8 ohms have too much down and up by 1/4dB starting in less than 10kHz. My Rowlands 200ASC is a little better - it dives down about 1/4dB but comes back to 0dB at 35-40kHz. Phase shift over 20kHz is also smaller - effect of higher carrier frequency.

Mapman - I was turning everything OFF but now I have Furman Elite 20 PFI conditioner with non-sacrificial over and undervoltage protection and keep everything ON all the time. It clamps at much lower voltage than traditional MOV protection.

Another very good brand of class D amplifiers is H2O Audio. They use ICE moduals but are powered by a very beefy torroidal transformer based power supply.

I've recently tried the H2O mono amps driving the Magico V2 speakers. They mate very well together. Better I think, from a synnergistic standpoint, than the Pass XA100.5 mono amps because of the extra bass control and frequency balance. In general I don't think that the H2O amps neccessarily sound better than the Pass XA100.5, but in the case of the Magico speaker wanting power and control, the match with the H2O amps was very, very nice.

You may want to check out the Digital Amplifier Company's products. Many users have commented about the superiority of the DAC amps relative to ICE and UcD amps from Channel Islands, Wyred, etc. Massive linear pwr supplies.
While I am friends w/ the owner, feel free to take my comments w/ a grain of salt but there are many happy customers who have moved on from ICE/UcD much like the Spectron users have.
I'm still waiting to do a direct Spectron vs. DAC comparison.
"Tube pre before Class D" is a good mantra!

-Mike

Anyone tried the Red Dragon M500 or M1000 monoblocks?

While I have certainly not tried them all, I have owned and/or listened to a few/several. Actually liked the initial sound, but over time I grew tired of them and was disappointed the more I listened to them. I think, or at least like to think that there is a great future with them. However, I am a bit suspicious of the wide pricing range and the super megabuck versions in terms of improvement over many of the more moderately priced ones.

So in the end, I am not currently/presently sold on their sound/performance and found them lacking for my expectations in too many areas.

Whether right or wrong, I have found that with virtually all components I have tried (quite a few), that the bigger and better the power supply side, the better the sound. So far, I have found this to be true with Class A and tubed amplifiers as well.

My suggestion for those considering the Class D amps is that very extensive (lots of time) listening be performed prior to purchasing, preferably in one's own system. I think they deliver a generally appealing sound initially, but I myself found the ones I have auditioned and owned lacking in the longer run. Perhaps my sound goal differs from others, but for my tastes this was/is my experience.