Can someone please explain

What you mean when you say (whether it’s a speaker or amp or preamp) it’s darker or warmer or softer or leans to the brighter side of neutral? Are you talking about how ss compares to tubes to class D? Analog to digital? How do you know what "neutral" is? How do you not know it’s actually in the recording? 
Curious minds/ears want to know.
some mussels definitely are, but their function is not always congenital... the Musculus Cremaster is good example :))) 
Takes balls to even mention that one. 
A great example how an honest and  innocent question, in this case of sound quality can turn. From soup to nuts ....
Don’t pay attention to distracting little details. The main point is congenital factor of sound perception.  
When I look at a painting I generally view it as a whole creation.....not individual components of paint colors/textures, tints, composition, view angle, etc. (abstract stuff too).
With music, for me, the same thing goes....and I either actively engage with it or don’t.
Hear the music and decide on a macro level or drive yourself crazy.
I’ll never be unequivocally sure what the artist intended and/or what happened in the daisy-chain between the creation and my ears.....but I do know if I like it or not.
I’ll probably be banned for saying this, but please try to ignore what you MAY be missing (really or not) and just enjoy the pleasure of experiencing the music with what equipment you’ve got.