Short List of Amps I prefer over the Pass Labs XA25 or INT 25

@atmasphere , thanks for your comments. I am too far from understanding all this technical background, but am learning some new things. I would not ask you many questions, but please forgive me if my understanding of these things is too far from the reality and my questions  are stupid. 
Feedback is not the only way amps can give the gane? 
Somehow class d amps use double feedback  to get to the switching waveform to transform analog sound to digital one? But how digital amps transform that digital sound back to analog (do they have some integrated DACs)? 

Feedback is not the only way amps can give the gane?
Somehow class d amps use double feedback to get to the switching waveform to transform analog sound to digital one? But how digital amps transform that digital sound back to analog (do they have some integrated DACs)?

You have to have gain to be able to apply feedback to an amplifier design. The feedback kills some of that gain and how much is measured in dB (decibels). But you still need gain for the amp to amplify the signal, so overall the circuit needs enough gain for that and the feedback.

Class D amps are analog, not digital. There is confusion because of the 'D'; it does not stand for 'digital'. Class A, B, and C were already taken when the idea was proposed in the 1950s.

tried to listen to a pass amp at last AXPONA.   unfortunately their display was static and visual only.  most unusual at an audio show and highly disappointing.  
i see a lot of them listed for sale, dis-proportionately so.  compared to the bigger players i have heard incl. jadis, parasound halo, mac ss and tube, esoteric, luxman a and ab, rega, hegel, line magnetic, primaluna, marantz, yamaha, bat, raven audio, cary ss and tube, manley, nad and more the only one i would take over my rogue audio integrated and seperates would be esoteric. 

Feedback is not the only way amps can give the gane?

It's "gain" as in "to add or receive." And feedback in linear amplifiers actually reduces gain. You can learn some of this with op amp text books.

Somehow class d amps use double feedback to get to the switching waveform to transform analog sound to digital one?

I'm not aware of double feedback loops, but I am aware of multiple types of feedback being used with different Class D designs.  As Ralph (atma) mentions, it's not digital, but the feedback controls the switching.

To be a truly digital amp the signal at least has to go through an analog to digital conversion, which doesn't really happen in Class D.  The control of the on/off switching is in the analog domain and that's where the feedback is used.

The latest Technics Class D amps may in fact be considered digital, as there is an analog to digital conversion at the input, as well as DSP applied for impedance compensation. These types of amps are quite rare. Many, including Ralph, argue that since the output is analog no audio amplifier can be digital.  I side with Technics though, it's sufficiently digital to be called a digital amplifier.

Rogue is made in my backyard..Bucks County,PA....Garbage. I implore you all not to listen to insane people destined for a padded cell.