High end Class D amps?

These things are great https://6moons.com/audioreviews/acousticimagery/1.html
The company went under. They sound in some way better than my 50K VAC amp.
Please give them a listen. 

@larry5729

answers to your why question:

- heat
- efficiency
- weight
- cost
- heat
- heat

RE:  Which of the following amps do you guys recommend for bluorion, who stated he "Can't afford" high end amps? 
Bel Canto

Jeff Rowland

Spec

Marantz Reference

Lyngdorf

The PS Audio Stellar M1200 Monoblocks are fantastic and at a reasonable price for the pair. I am driving a pair of Magnepan 1.7i with them and the combination is excellent. I believe a eview is coming out in one of the major audio mags soon.

 In general, solid-state (ss) amps reproduce deep bass frequencies better than tube amps. A good indicator of an amp's bass reproducing ability is its Damping Factor, which basically measures its ability to control, or start and stop, the bass driver. The higher the number the better its control. Class D amps usually have much higher damping factors than the other amp types; class D amps can be rated in the low thousands, class A and AB are typically rated in the low hundreds and tube amps even lower.

There really aren't any speakers that need more than 20:1 in a damping factor and some need considerably less. On top of that, traditional solid state amps actually have enough feedback at bass frequencies to do the job (whereas they usually don't at high frequencies, which is why they are often bright and harsh).

I always thought pure class A amplification was most ideal. So why manufacture Class D amps?

Class A is all about the output section- keeping its distortion as low as possible and its quite effective. But this says nothing about the input section and driver circuitry, and the output section is still going to make some distortion (just less than if the same circuit were class AB or B).

Class D uses a different means (switching) to make power, and so does not make distortion in the same way. There are basically two means that the amp produces distortion- the first is how accurate the encoding scheme is. The second is caused by the fact that the output transistors take a finite period of time to switch on and off and so to prevent damage to them, a bit of waiting is done to allow one device to shut off before the other is turned on. Otherwise current can shoot through both devices, heating them up quickly towards failure. This waiting time is called 'dead time' and contributes to distortion. The distortion signature is different from traditional solid state and does not tend to be bright. Instead it tends to have more lower harmonics like tube amps, and not surprisingly  can sound a lot like a tube amp, except when the amplifier is overloaded.  Certainly the reduced amount of heat is an incentive- this is the main argument against both tube amplifiers and class A amps and especially class A tube amps  :)