The better solution isn't adding to the top of the tenon of the long joint, but a shim that you have inserted into the socket on the boot. This way you don't get a disturbance in the bore that looks like
For stability you'd have a matching ring on the long joint as well, but that's not where the acoustic should be set.
I don't personally find that adding a little length there does all that much to most bassoons, at most it affects the low E a bit, but that's mostly all. I know you didn't ask for that advice but I felt compelled to put it in.
Still, these aren't something you simply order, they have to be custom made to your instrument by a repair technician.
Last edited by Trent (2015-10-01 10:56:00)
M.M.A., D.M.A. University of Illinois at Urbana/Champaign: B.Mus. Lawrence University
Bassoon professor at University of Wisconsin Eau-Claire
Maker of the Little-Jake electric bassoon pickup and Weasel bassoon reeds