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Has anyone cut down the 5th slide on a Gronitz pf-125 in order to make it a flat whole step configuration. If you have, could you post a picture from the back side of the tuba? Does Gronitz produce any with a flat whole step 5th valve?

Any comments or suggestions welcome.

Thanks.

John Bottomley

Just curious. . .What's a flat whole step? Is it a whole step minus some %, or is it 3/2 step down?

it's a whole step plus some. for ex: when playing the fundamental F, engaging the 5th valve will cause a FLAT Eflat will sound.

-CT

Gronitz builds tubas to order with any 5th valve tuning you would like. Flat whole step is the standard now, but most anything is available.

SF

sailn2ba wrote:Just curious. . .What's a flat whole step? Is it a whole step minus some %, or is it 3/2 step down?

As you might know the 3 first valves of an F tuba will lower the tuba to respectively Eb, E, and D. The 4th valve lowers the F tuba to C.

It is possible to descend further down from that C, but the problem is that the 3 first valves are tuned in relation to the main bugle in F. They are too short for the virtual tuba in CC consisting of the main bugle plus the tubing of the 4th valve. You could add 3 or 4 valves more to fit this virtual CC tuba, and something like that has been done in very rare cases. It never became common, as such bulk of valve tubing is heavy and clumsy. Compromise was asked for:

One more valve was added, which lowered the combined CC tubing one whole step. This valve can be used in many funny contexts, but its main purpose is to lower the combined tubing of the main bugle plus the 4th valve loop one whole step further down. The length of that tubing will lower the main tubing around 1 + 1/3 step, if only the 5th valve is activated. Hence the naming: long whole step or flat whole step.

Klaus Smedegaard Bjerre

I own a Gronitz PF 125 with a flat whole-step fifth valve. As far as I know this set-up is the most common. They do offer it with the tri-tone, but I don't think there are a lot of those around.

If you have any other questions shoot me a p.m.

My 125 has a tritone 5th valve configuration. The slide for the 5th valve has two parts, a crook at the end which can be removed from a longer section of tubing for the tuning slide. If just the crook is used the 5th valve becomes a two whole step configuration. I think the tritone set up works better on the horn. I'll see if I can get some pictures up here today.

If just the crook is used ,it makes (short) two whole tones.
For fingerings look at http://www.gronitztuba.de" target="_blank
(tuba specials)

As I had to work with the contrast anyway, I add this partial Gronitz fingering table concerning the use of a 5th valve lowering the main bugle 2 whole steps.

K

The first ones I imported had the tritone valve, which could be switched to the old short 2&3 config. I tried to get used to the tritone config, but never could find a decent fingering for low Bb. All of the new ones have the long whole tone set up.