OP- you may want to start here.
https://forum.audiogon.com/discussions/my-long-list-of-amplifiers-and-my-personal-review-of-each
Like most audiophiles seeking answers such as yours, there is mud and sludge one must go through reading all these experiences with all these amps to find some answers. This guy (who started the post above) has stated he had the opportunity and resources to do much of the work and has tried many quality amps. So it’a good read, to say the least.
https://forum.audiogon.com/discussions/my-long-list-of-amplifiers-and-my-personal-review-of-each
Like most audiophiles seeking answers such as yours, there is mud and sludge one must go through reading all these experiences with all these amps to find some answers. This guy (who started the post above) has stated he had the opportunity and resources to do much of the work and has tried many quality amps. So it’a good read, to say the least.