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Re: Tubing Lengths

Posted: Sun Jan 30, 2011 12:52 am
by imperialbari
If I had considered you a trustworthy friend, I had sent you my very private Excel sheet.

Klaus

Re: Tubing Lengths

Posted: Sun Jan 30, 2011 1:33 am
by imperialbari
Ein Gartenzwerg bleibt immer ein Gartenzwerg.

Re: Tubing Lengths

Posted: Sun Jan 30, 2011 2:23 pm
by sloan
imperialbari wrote:Please be aware that the leal length is shorter than the theoretical length due to effects of taper and flare.
Perhaps your "theory" should be expanded to include taper and flare?

Repeat after me: a bugle is not a string...a bugle is not a string...a bugle is not a string...

Re: Tubing Lengths

Posted: Sun Jan 30, 2011 2:32 pm
by Dan Schultz
sloan wrote:
imperialbari wrote:Please be aware that the leal length is shorter than the theoretical length due to effects of taper and flare.
Perhaps your "theory" should be expanded to include taper and flare?

Repeat after me: a bugle is not a string...a bugle is not a string...a bugle is not a string...
If you want to make it REALLY confusing... toss in the fact that the open bugle is actually somewhat less than HALF the actual fundamental pitch wavelength. Acoustics is so involved it's no wonder the only way to design a tuba is to build a prototype.

BTW... isn't a 'bugle' one of those conical-shaped corn chips? ... sort of like a 'rolled-up' Frito!

Re: Tubing Lengths

Posted: Sun Jan 30, 2011 2:35 pm
by UDELBR
I stopped contributing to threads like this when I started getting 'corrected' by traffic engineers. :roll:

Re: Tubing Lengths

Posted: Tue Feb 08, 2011 8:56 pm
by Tundratubast
This a great question.
I'm working on a project horn at Red Wing and am wanting to add a fourth piston and a fifth rotor, but my marketing & sales background have me clueless in determining the necessary lengths for the respective 4th & 5th slides, moving the tuning slide from the lead pipe to a post fifth valve position "should" be easier.

Sooo, where or what is an appropriate research resource for this particular issue. My guess is that each slide has to be a % of the bugle of the particular keyed instrument per each valve. My question than is where to find this information to study and apply. I'm working on a 1935 Buescher 3v, FA Eb with a 20" bell and stands about 36" with an estimated bore of .689. The bore was taken rather hastily, it is a small bored valve set.

Thanks in advance for any assistance and direction.
P.S.
I have taken the bottom bow cap off and have rolled the dents and dings out of both and have been able to reshape the cap to a proper fit and will be reapplying it and a wire later this week.
Yeah. :tuba:

Re: Tubing Lengths

Posted: Tue Feb 08, 2011 9:33 pm
by SousaSaver
the length of 4 will be roughly (but not exactly) a combination of 1+3. For the 5th valve I don't know. You could make it a flat whole step and make the tubing length similar to the 1st slide tubing.

Re: Tubing Lengths

Posted: Fri Feb 11, 2011 2:43 am
by pinedale
The "magic number" is my 3rd most favorite number (after e and pi), the twelfth root of 2 (in an Excel spreadsheet cell, type =2^(1/12)). If you want to drop the pitch by k well-tempered half-steps, multiply the length by 2^(k/12). Caveat: this doesn't account for flare/taper.