What is the best solid state amplifier you have ever heard?

I haven't heard that many and I tend to prefer tubes myself. With that caveat and the obvious fact I heard each of these with a significant amount of time in between and on completely different speakers/setups:

4) Sugden amps sounded really nice
3) Pass Labs XA30.5 (haven't heard the .8)
2) Pass Labs XA25
1) Nagra Classic Series sounded sublime

amp/speaker synergy makes too much of a difference to pick just one.

@steve59 

Exactly

I just recently acquired and have had the pleasure of "listening" to my 47 Laboratory Midnight Blue combo: the 4733 & 4734.  This set is special together but I have been recently using just the 4733 (Amp/Pre/headphone amp) with the newly arrived Sparkler Audio S301B diva' and what a spectacular combo.  I still cannot believe the quality & quantity of sound reproduced with only 2wpc...I have finally found what I was looking for in a small system.  so, my short run of solid state amps, integrated, etc has come to an end (maybe).  Thinking about what a Sparkler Audio Ether @ 7wpc would be like...Here we go again...
Cheers

I know this is a little obscure but my 30 year old Mirror Image Audio 1.1 SB power amp is the best SS I’ve ever heard. It was very expensive at 5k in the late 80’s, early 90’s. Occasionally you will see one for sale.