Posted by Chuck(G) on November 07, 2002 at 11:28:20:
In Reply to: Re: Low Pitch/Modern Pitch posted by Rob P-M on November 07, 2002 at 10:12:45:
I assume you mean 432 Hz, not 332. Otherwise, you probably don't have an Eb sousaphone.
Before you take the hacksaw to the horn, I'd check for leaky valves, joints and waterkeys. A small leak can have a substantial effect on pitch. If your valves are leaky, try sealing them up with heavy oil or grease to get a good seal. If this improves matters, get the valves redone, then reassess your horn.
But if everything's tight, and you feel a need to take some tubing off, start with the main slide. Eb2 at 20C has a wavelength of 441.4 cm at A4=440 and 449.6 cm at A4=432. So you should take off about 8.2 cm from the tuning slide or about 1.5 inches from each leg.