Hello. Never really gave this a thought until purchasing a pocket trumpet and noticed the options...
I assume that a horn's key ( B-flat, B, etc.) is determined by tube length. However, what is used as a benchmark tuning source?
Playing "B-flat" on my piano equates to a "C" on my B-flat horn. If I had a "C" horn, what's the equation?
What's the reason (advantage?) of different keys? Ease in playing a piece in a difficult key signature?