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

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. 

I don’t really know or care much for specs. Voicing of any component is, to me, most important. For a designer to be a musician is not necessarily prerequisite but it helps. Vital is that the designer not only needs to understand what music sounds like but is able to voice their “instruments” reflecting that knowledge. Then, ultimately, an amp/speaker combination needs to reflect the taste of the listener. Obviously, an amp can only be evaluated when powering a speaker-the “two hands clapping” in any system.

It is then an interdisciplinary thing, very desirable but perhaps it rarely happens an engineer to be a musician, but it will help if he is an audio fan.  

Eric, i thought feedback was something to create the gain. I am too far from this field, but will try to have a look on some books (e.g. why the feedback is unavoidable). 

Could something similar to  switching waveform be used to create a correct and accurate digital signal from the source analog signal and "amply it digitally" without any distortion? Is there no way to amplify a digital signal directly from the digital sources (e.g., CD player), what this would really mean? Then you will again need a DAC just to output the amplified digital signal to the speakers (but i understand that "amplified digital signal" cannot exist, a binary number cannot be amplified and that  that the conventional amplification is analog).  

I was not aware of Technics class D players which is interesting. Cherry amps are produced by a US company called Digital Amplifier Company (DAC), there should be some reason for this name.