SS Amp for Avalons

Spencer, yes, as are MFA and Bob Carver Tube. These are the only tube amplifiers I've had direct in home experience with. Purchased used and considering their quality they could be considered affordable.

In the case of Carver his personality, marketing, and the pedestrian look of these amplifiers, some might make a costly mistake by removing them from consideration especially in KT150 livery.  
 
I have no in home experience with other speakers in the Eidolon or Diamond price range. My experience with the Eidolon/Diamond is the complete opposite from yours. This is the first time I've heard them referred to as overly detailed or etched so I'll defer to your experience here. 

Aren't Ayre & VAC both made in USA? 

It's true that Avalons are revealing & everything matters. Compared to many other speakers some might call them overly detailed or etched, especially when matched with ss electronics. My ownership experience with them was short because that combination left me fatigued and drew me away from the music not towards it. All the engaging Avalon experiences I've had since have all been with a variety of tube amps.
Don't let a short dealer demo with ss electronics, backed by rave magazine reviews be the only listening you do before going that route. Learn from my mistake. Cheers,
Spencer 

For years I never did get the Avalon presentation at shows but in the first ten minutes of listening to my standard Eidolons at home I got off the merrygoround. 

I've herd them powered by Ayre V-1xe stereo, MFA D70 stereo, VAC Phi200s, freshend up MFA M-200s, and Carver VTA180s all off their 4 ohm taps. Unfortunatly, I was unable to do side by sides comparisons of the tube mono's.

The D70 demonstrated the need for more power for listening approaching realistic levels. I agree with siddh these are revealing speakers were everything matters. Even though the three high powerd tube mono's each have their own presentation my poor sonic memory prevents me from picking a favorite so I picked the ones made in America. Does that help?

Use the spikes, that port needs to breath. 

The CAT amp may have all the power and finesse, depending on room size and music preference.  I heard Ascents driven by Gryphon amp.  It was unforgettably good.  I have found the Diamonds to be revealing, requiring careful component and cable matching.  

my favorites are Ayre and Audio Research

Although I've owned Avalon/Spectral and heard it many times at dealer, I preferred Avalons with BAT tube monoblocks or Atma-Sphere monoblocks. The BATs had more bottom end power but the MA2s had a great mids & treble particularly on acoustic instruments and classical music. If you are a rocker, BAT might be a best choice. If SS, I agree that Symphonic Line and Pass are some of the best options. Cheers,
Spencer

Symphonic Line Kraft monos for solid state.

For tubes, I have not heard anything that beats the CATs with Avalons.

Avalon Opus w/ Spectral 360s They like power!! Speakers are as fast as the amps

Pass XA series very nice indeed.

I have heard Ayre with them. Sounded fine.