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

How do you isolate the amplifier? It's a system and every component, including the room impacts the sound. 

To the OP

(1) ricred1 nailed it ....full stop

(2) there is no “best” in isolation because of (1) 

(3 Without prejudice to (1) and (2)  above you already have three current posts and all with the same core theme

https://forum.audiogon.com/discussions/what-is-the-best-solid-state-amplifier-you-have-ever-heard

https://forum.audiogon.com/discussions/pure-class-a-amps-above-100-watts

https://forum.audiogon.com/discussions/best-integrated-power-amplifier-under-6000

Bedini 25/25! I still have mine. Bought in 1980 from Innovative Audio in Brooklyn Heights, NY. Cost - $750. Used it with Quad 57's. A forgotten classic!

@roberjerman, I used that same combination myself for years, but sold my 25/25 about a year ago. Another worthy contender is a pair of BEL (Brown Electronic Labs) 1001 Mk. V's, ay? The only solid state amp Brooks Berdan liked and sold (he was enough of an idealist to insist on the former before agreeing to do the latter).