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A week ago, I got a old Bbb 3v compensated Boosey & Hawkes. Plays well, but there is a high frequent buzzing in the background, to hear while blowing pianissimo or when a tone ends. It ist not very loud, but it disturbs me, and it is over the whole range. Loose solder points I can't find.
Does someone knows this effect with such Booseys and how to eliminate this?
Ulli

Wade, David, Adam,
thank you for your advices.
I inspected the tuba again and noticed a hair- rip in the tuning bow.
After I had soldered the rip, the problem is solved.
Ulli