Adding a fourth valve to a tuba?

[MStarke]

I am somehow tempted to buy a cheap Besson 3 valve compensating e flat tuba with piston valves which seems to be in comparably good condition.

Not sure if I really want to do it, but hypothetically:
I am pretty sure I would want to add one more valve to reduce the number of notes that don't sit well on it.

What tuning should this be?
- a perfect fourth seems logical as it's how normal fourth valves are tuned
- a low fourth could be helpful to make the a flat in tune with 1 and 4
- however a perfect fifth could also be great in my opinion
What woyld you do?

Would you add a rotary or piston valve? Piston would probably be expected, but as a trombonist, I prefer rotary in general.

And any guess what this could cost (very rough ballpark)?

[elmsandr]

I'm thinking of adding a 4th and a 5th (flat whole step) to mine.

Join the "Frankentuba" Facebook group for a lot better opinions.

Cheers,
Andy

[hyperbolica]

There are a lot of existing 4 valve tubas. The 3v comps do have a great reputation, though. Adding a rotary allows you to place the lever where you want it, but requires you to add a lever. Piston doesn't require the lever, but can be more difficult to place. You should probably count on the valve to cost +/- $1500 if you have a pro do it. Also depends on if you source a new or used valve and tubing.

Most 4th valves are a P4, but if adding this to the 3 comp, it might make sense to make it a long P4 for non-compensated combos. My preference is for a tuning trigger on the mts to take care of tuning issues like a trombonist would.

[Doug Elliott]

There are tuba techs who do that sort of thing a lot. They would have good insight into what works.
Ask the question on one of the tuba forums if you haven't already.

[heldenbone]

There are tuba techs who do that sort of thing a lot. They would have good insight into what works.
Ask the question on one of the tuba forums if you haven't already.

It's been a few years, and he would probably deny everything, but Lee Stofer added an F attachment to a soprano trombone for me, sourcing the tiny rotor and slide as a unit from Rudy Meinl. I recall the total cost (parts + labor + sense of humor) as having been in the neighborhood of $800.

[Doug Elliott]

That's very cool... But I rest my case. A trombone tech would have made different choices.

[Finetales]

I've actually put some thought into this exact question (and posted about it on the Tuba Forum already!).

A 3-valve compensating set is basically the valve equivalent of a trombone slide, as all the combinations (=slide positions) are pretty much in tune. So if a trombone with a valve in Eb has valve positions that match up with open positions, that means in theory that a 3v compensating + perfect 5th setup will also be in tune all the way down. I tested this when I had my stock single-valve 72H, as the valve can pull to very nearly Eb (Eb is just off the bumpers). I found that the Eb valve notes (Eb-B1) are either exactly on an open slide position or very close, and easily lippable if you don't move the slide to the exact right place. So in theory, adding a perfect 5th valve would give you a fully chromatic instrument without the need for slide pulling or much lipping.

Of course, you could always try both and see what you like. It wouldn't be too hard to make the valve a 4th with an extender or different slide to get a 5th.

[Vegasbound]

www.m-j-c.co.uk

Mike Johnson has been doing this stuff to tubas since 1997, take a look at his valve etc, his website is above.

[MStarke]

Thanks everyone!

I also considered looking into a tuba forum, but am really hesitant to go there

That is all some great information.
If I would go there, I would probably go with a 4th valve giving a perfect fifth (as described by Finetales).

However taking that input into consideration and also having taken another look at the instrument, I will most likely not do it now. This particular instrument also doesn't seem to have an obvious spot where to place the additional valve appropriately.