My Medium List of Amplifiers and my Personal Review of Each !

Cool list that a blue collar music lover can afford. 

I think it's great that you're doing this. However, based on my experience I think it would be appropriate for you to also tell us what your power situation is and what interconnects and wires you're using. Like whether you have a dedicated line or not, stock power cords, any noise reduction stuff, power conditioner, etc. 

My thoughts are that "none of this should make a difference" but what the heck. It does. If your power/cords/interconnects/wires are holding you back or are unique in some way they could be imparting a character to what you are hearing that you are attributing to the equipment.

Just a thought. Not trying to start a flame war.

I am not sure what your budget is in this process.  Given the economic environment, probably less now than a year ago.  A couple of amps that you can find on the used market would be interesting....Luxman 509, Canary Audio M80 or any of their line, Gryphon 120 integrated.  

Update to the list.

OUT- Dual Mono Benchmark AHB2 

IN-Pass Labs XA 30.8

Reigning Champion- Pass Labs XA25

The Benchmarks sounded really good but I believe were a gain miss-match with my Cary Audio preamp.  This resulted in lack of refinement and a forward midrange that had too much energy. No matter what I did I could not get happy with the sound.  

The Pass XA25 is still the reigning champion with its clear yet super sweet and refined sound.  Such an awesome amplifier.  

We will see how it compares to the up range Pass XA30.8.  More to follow...

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INTEGRATED AMPS

NAD C356 BEE - not bad but not as smooth as the Yammies, Cambridge Audio or Marantz in its range. Sounds strained at volume even with 89db speakers. Relatively unrefined.

Raven Audio Nighthawk (tube) Nice sound, very transparent and refined, powerful beyond its 20 WPC, good value, sound quality is highly dependent on NOS tubes.

Raven Audio Blackhawk. More refined and transparent than the Nighthawk, use with efficient speakers and it could be a forever amp. Super colorful high end sound, again depends on tube choices.

Rogue Audio Cronus Magnum II

Powerful and dynamic with an atmospheric sound stage. Responds well to NOS small signal tubes, KT 120 power tubes are fantastic. A sound that belies its modest price, beats many more expensive amps.

POWER AMPS

Cary Audio 200.2. Very powerful and supremely dynamic and transparent amp. Midrange forward but with extended deep bass and highs. Starts and stops on a dime. Treble can be slightly unrefined at the top, midrange can be too forward sounding, best to match with darker speakers.

Rogue Audio Stereo 100. A dynamic powerhouse. Even with the same 100 WPC spec as the Cronus Magnum it sounds much more powerful. Excellent bass slam, very refined when the tubes burn in, even better with NOS small signal tubes. Huge sound stage. Excellent value, lacks the ultimate transparency and refinement of the Cronus Magnum.

Parasound a21+. Super smooth and engaging sound, good bass and refined treble. Definitely not as fast, transparent or dynamic as the Stereo 100.

Pass Labs XA25. A gem of a sweet sounding amplifier. Not as transparent as the reviews lead you to believe but awesome sounding nonetheless. Extreme micro dynamics and instrument separation, lots of contrast between sound levels of various instruments, almost as if each instrument had its own channel and speaker. High degree of refinement. Very good power that goes well beyond its modest rating. Warm yet detailed, this one could be a keeper for anyone with moderate to high sensitivity speakers.

Parasound JC5. Recent acquisition and a really impressive sound. It literally does it all- smoothness, extreme transparency, most transparent amplifier I have heard. Lots of power yet sounds amazing at low volume. Effortless dynamics, sounds flow abruptly at high contrast levels. Best midrange I have heard- no coloration at all. Excellent bass depth and slam, biggest sound stage of any solid state amp I have heard. Dark backgrounds that are noticeable by their silence. Absolutely love it.

Final update: 

Update to the list.

OUT- Pass Labs XA25

IN-Pass Labs XA 30.8

Reigning Champion- Pass Labs XA30.8

After letting the Pass Labs XA30.8 settle in and worked in to my system with cable tweaks and other adjustments it was clear what this amplifier was all about compared to the champion Pass XA25. 

First off the XA25 is not as transparent as the reviews would lead you to believe- at least in its year old well run in form.  The XA30.8 is noticeably more transparent and open with more extended treble.  The midrange transparency is literally end game for me.  The XA30.8 also has more power range and less midbass bloom.  Deep bass is also very strong on the more powerful 30.8 

The XA25 is a warm, sweet dynamic amazing sounding amplifier but ultimately a touch too colored in my system.  The XA30.8 is here to stay.  Class A refinement, power, bass control and tube amp transparency and sound stage.   

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INTEGRATED AMPS

NAD C356 BEE - not bad but not as smooth as the Yammies, Cambridge Audio or Marantz in its range. Sounds strained at volume even with 89db speakers. Relatively unrefined.

Raven Audio Nighthawk (tube) Nice sound, very transparent and refined, powerful beyond its 20 WPC, good value, sound quality is highly dependent on NOS tubes.

Raven Audio Blackhawk. More refined and transparent than the Nighthawk, use with efficient speakers and it could be a forever amp. Super colorful high end sound, again depends on tube choices.

Rogue Audio Cronus Magnum II

Powerful and dynamic with an atmospheric sound stage. Responds well to NOS small signal tubes, KT 120 power tubes are fantastic. A sound that belies its modest price, beats many more expensive amps.

POWER AMPS

Cary Audio 200.2. Very powerful and supremely dynamic and transparent amp. Midrange forward but with extended deep bass and highs. Starts and stops on a dime. Treble can be slightly unrefined at the top, midrange can be too forward sounding, best to match with darker speakers.

Rogue Audio Stereo 100. A dynamic powerhouse. Even with the same 100 WPC spec as the Cronus Magnum it sounds much more powerful. Excellent bass slam, very refined when the tubes burn in, even better with NOS small signal tubes. Huge sound stage. Excellent value, lacks the ultimate transparency and refinement of the Cronus Magnum.

Parasound a21+. Super smooth and engaging sound, good bass and refined treble. Definitely not as fast, transparent or dynamic as the Stereo 100.

Pass Labs XA25. A gem of a sweet sounding amplifier. Not as transparent as the reviews lead you to believe but awesome sounding nonetheless. Extreme micro dynamics and instrument separation, lots of contrast between sound levels of various instruments, almost as if each instrument had its own channel and speaker. High degree of refinement. Very good power that goes well beyond its modest rating. Warm yet detailed, this one could be a keeper for anyone with moderate to high sensitivity speakers.

Parasound JC5. Recent acquisition and a really impressive sound. It literally does it all- smoothness, extreme transparency, most transparent amplifier I have heard. Lots of power yet sounds amazing at low volume. Effortless dynamics, sounds flow abruptly at high contrast levels. Best midrange I have heard- no coloration at all. Excellent bass depth and slam, biggest sound stage of any solid state amp I have heard. Dark backgrounds that are noticeable by their silence. Absolutely love it.

Benchmark AHB2 (Single and Dual).  Obviously the reputation this amplifier has is nothing short of stellar so I had to give them a go.  Not quite as refined as my reigning champ the Pass Labs XA25.  Excellent power and bass.  Dynamics were the deal breaker and not in they way you might think- they were too dynamic, hyper dynamic actually, even using a single amp.  They sounded loud even at low volume levels which is hard to describe in words.  Also too forward sounding in the midrange.  Ultimately I had to move on.