I make all these changes to my system from day to day or so and usually, with me anyway, I think "ok, well...not sure if it made any difference".

When I notice that it sounds really good (or bad??!) is usually the time when I'm not paying any attention and messing around with something else. I think to myself "damn, that sounds really good!"

I also play different types of music to get a better idea of how my system is performing.
I'm mostly a punk/hard rock type but I like playing some jazz now and then, as an example, because a lot jazz has solid clean sounds and I can evaluate my speakers better. Funk too...

Just wondering....

EDIT: I just have to say that I posted this at 4:26 today and that's a 426 Maxwedge in my avatar, LOL. Weird