You will have to listen a lot more to a lot more gear.
It is puzzling that amplifiers that by all logic 0.0...X % and 0.0X dB and comparable power can subjectively sound cold or warm . The amps that invariably got "cold" from me were Spectral designs - and it was opinion of every friend that ever got the chance to listen to it. Just as if not more detailed is amplification from Swiss Physics - which you could most easily equate with the cozy warmness of a vintage fireplace.
By the definition of "all amps sound the same" camp there should be zero difference in sound between the two - but there is. And under no circumstances it can be pinned down to a SINGLE parameter - another thing that bothers me with "science". Always trying to boil down things to a single factor. I get it is easier to monitor etc - but it is seldom applicable in practice. Better performance in one parameter usually means worse in another - and it is balancing with many balls with the prime task of not letting down even one - despite other X not travelling in so high circles or whatever if one was let to fall to the floor.
I have spent some two years in order to make my amp for ES headphones really sounding good. If you asked practically all electronic engineers to look at the schematics, they would say NO difference.
You should have seen the faces of VERY FEW selected friends ( the amp is lethal - no joke, this had to be well understood before they were allowed to come anywhere near ) at the beginning and the final stages of the project. From
or meh - all the way to
.