When my son joined the N.D. National Guard Band, he was issued a Shires trumpet even though he had two great horns of his own that he really liked. The entire trumpet section plays, is asked/required to play, a government-issued Shires trumpet. Near as I can tell, this is the policy for all military bands. Band members are issued government horns, presumably the same brand for each band and each section. I am told this is, at least in part, to facilitate a blended sound. There may be, likely are, other reasons. (I know that the guys playing on the Guard's pay appreciate not having to risk damage to their personal horns).
Do the major symphonies (Boston, Cleveland, New York, Chicago, Minneapolis, ect) require/ask that the trombonists play the same brand of horn? Who decides? Is it true that Bach and Yamaha are the most commonly chosen trombones by major symphonies? By what percentage (ball park guesses accepted
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Or does each player chose his or her preferred horn?
Do Bach and Yamaha dominate?
(I have an impression, based on no personal knowledge whatsoever, that Bach is the aging king and Yamaha is the young challenger to the throne)