I recently read a blog post about "clocking" your mouthpiece, i.e, moving it around like a clockface to see where it plays best. It was a trumpet blog, but I'm wondering if it would apply to euphonium mp's as well, or does it really make a difference at all. I experimented with my euphonium mp's and couldn't tell a difference. It did recommend having someone else listen instead of trying to discern differences yourself, which I didn't do.