The physics of sound have been explained by many people but the relationship of practical applications are a blur. I am a brass instrument player and designer of bras instruments the relationship between bore size, taper and length are very crucial and way over most peoples head. so here is the question.on the latest trumpet prototype,with a bore size of .460, there was a bore size restriction in a few areas(specifically where the knuckles left the valve section) of .005-.010 of an inch. The result was pitch went flat in quite a few places. when the bore size was corrected to the correct size of .460 the pitch went in tune. can some one explain or is it even possible to explain in laymen terms?