I had an audio manufacturer (now friend) visit my home and listen to his gear that I owned in my office system. We played music by musicians he was friends with and knew how they should sound. After that session he gave me a lot of constructive criticism. I ended up rearranging my room and selling some gear. I did also sell the 2 amps he loved the most and kept the amp he liked the least. That was because I knew we had some slight differences in our audio sensibilities.
A few months later, I was proved correct in putting my faith in his musicians’ ears. There was a writeup on his great listening skills on 6Mooons.com
My room has never sounded better.