Most likely, an amplifier designer uses 3/4 different pairs/types of speakers...to voice his amp so that it sounds like he wants it to sound....neutral, lush, forward, whatever... And his voicing may or may not be to your liking...
And, if you have different speakers, electronics, room, etc., then what you hear is going to be different....maybe to your liking and maybe not.
It is not a case of right or wrong, it is a case of preference and the reality of synergy...and why we often have to go through several pieces of equipment to find what works well together to deliver the sound that speaks to us.