harold wrote:If the horn is consistantly 20 cents sharp with the first, how much shank will I need to reasonably get this horn into tune with the second?
More than what is possible, based solely on length. But the shape of the mouthpiece can have its own effect. A smaller cup volume has a higher pitch tendency, as does a larger throat. My Besson euphonium is noticeably flat with any mouthpiece except the Wick/Mead, and I doubt the quarter inch difference in insertion is the reason.
Proper insertion isn't so much of an intonation issue as a response issue. It might affect intonation a bit, but I doubt systematically.
Rick "whose tubas' intonation doesn't seem to vary much with mouthpiece insertion" Denney
As Rick said, the interaction between the mouthpiece and the horn is complex. Perhaps you should consider a "tuning bit" between the mouthpiece and the horn.
To give you general information on pitch and tubing length: If you remove about 2.3 inches of tubing from a CC tuba, it will play about 20 cents sharp. Adding the same length makes it about 20 cents flat. For other pitch tubas, you will have to scale that figure up or down. Moving the main tuning slide about 1.15 inch will have the effect of changing the overall tubing length by 2.3 inch.
A comment on the measuring unit "cents": A semitone pitch difference (in equal temperament) is defined as 100 cents. You could call cents the same as percent of a semitone. In the case of A=440Hz, an A that is 20 cents sharp would be 445.2Hz. Note that this pitch difference resembles the pitch difference between standard pitch that is usual in the USA, and European (and some USA) orchestra pitches. Some tubas are available with alternative main tuning slides to accommodate this difference.
I have played my Besson with everything from its own Wick 1 which seats all the way as it should, to standard American shank mpcs which go in @ 3/8 inch, to Euroshanks that barely fit (just to see what they sound like to see if I wanted to order one in the correct size). Here are my observations:
Between a Wick 1 British shank and a Bach 18 American shank, it must be the bowl or throat/backbore characteristic, because I didn't have to move the tuning slide at all to still be in tune. With all others, the most I moved the tuning slide was about an 1/8 inch, regardless of the difference in the shanks.
Ironically, between a Wick 1 and a Wick 2, same shank, I did have to move the slide to get back into tune.
Allen wrote:As Rick said, the interaction between the mouthpiece and the horn is complex. Perhaps you should consider a "tuning bit" between the mouthpiece and the horn.
I did and it worked for me.
Marzan BBb
John Packer JP-274 euphonium
King 607F Posting and You
I'm guessing you have an American shank mouthpiece and are wondering if the Euro shank version of the same piece will lower the pitch enough to make it worth buying (or something like that) ??
You could try somthing like this:
Play the tuba with the first mouthpiece. Mark the main tuning slide with a pencil, pull it out until it's in tune and mark the slide again. Measure the difference between the marks, you'll need twice that much. If it's a LOT, no standard mouthpiece is going to help enough.
Or, you could do some experimentation with mouthpiece A (assuming you only have the one) and a roll of electrical tape. Shouldn't take too much tape to make up the difference between an American shank and a Euro shank. This post by Matt Walters would be helpful in that situation:
Any store that serves marching bands that have sousaphones will sell tuning bits. Two are required for sousaphone, and they are regularly lost. The Conn/King bits are the same size going in and out, and work in general application. Any Conn-Selmer dealer should be able to order them for you.
Rick "noting that some tuning bits are customized for application" Denney
I played next to a guy who added a tuning bit to his King 2341 tuba. He was very happy to solve his general sharpness problem this way. By the way, that's a really good BBb tuba.
iiipopes wrote:On some older Kings, the bits can be two slightly different sizes; but I believe all the newer ones are the same size.
Hey, guys: weren't some models of older Conns actually supplied with a bit a part of the way they were made to intonate properly?
The Conn 2xJ tubas were designed to be used with one tuning bit. I also recall that Martin top-action BAT's used two bits, but my memory is that they are special to that application.
Rick "who has played a number of tubas with a tuning bit and no ill effects" Denney
