Rotary compensator

[MaryAnn]

Can someone tell me why there aren't any rotary compensators out there? There must be a physical reason but I don't know what it is.

[SplatterTone]

I think the extra ports to control the extra plumbing would not work with rotors that are simple switches for route A or route B. You will need rotors that control multiple routes at the same time which, I assume, would require rotors of big enough diameter to have channels through the rotor; or rotors tall enough to control control multiple ports.

[bort]

Timswisstuba once sold a rotary compensating Hirsbrunner BBb here. I don't remember anything about it, except that it exists.

Are there others? I have no idea...

[eupher61]

Hirsbrunner holds a US patent for a compensating rotor. it's been years since I saw the patent, but it was a big rotor. I'd imagine that's where the ill-fated synthetic insert valves began. The one that Tim sold. is the only one I am aware of.
you'd think that with 3d printing something could be tried again...maybe titanium.ultimately?

[Mikelynch]

There are other rotary compensators out there. The Cerveny and Alex double tubas (and other similar rotary instruments) are essentially rotary compensators, albeit with a different magnitude of compensation than what we normally thing of as a compensating tuba.

John Fletcher worked with Yamaha on a rotary compensating F tuba for several years. The last version was less than a complete success, though it is playable with some work.

One difficulty with any configuration where the rotary valve has to span two sets of tubing is the mass of each valve (and the resulting friction), and the resulting tendency for them to move relatively slowly as a result, at least with conventional paddle leverage and spring strength.

Mike

[nycbone]

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[imperialbari]

Hirsbrunner made 3 valve rotor compensators in BBb, where only the first 2 rotors were double storied. They made a similar instrument in Eb, only there was an added 4th valve with no involvement in the compensating system.

The Alexander double tubas have the shift valve right at the end of the leadpipe, which makes very little sense, as the wider bore CC or BBb compensating loops are earlier in the airpath than the smaller bore F valves. Leading to a regressive step-bore.

Kruspe made a compensating double tuba similar to that of Alexander. Only I don't know about the bore progression through the valves of the Kruspe version.

Kruspe also made a 4+3RV double tuba in F and BBb (Doppelbaß in F und B) where the 4th valve in the left hand was the shift valve.

All of these are represented in my brass gallery. The index is in the Files area

Klaus

[iiipopes]

Yes, to order, Hirsbrunner used to make (I don't know if they still do or not) a BBb 3-valve compensating double-rotor tuba. Here is the picture I got when I emailed them asking about it some years ago. I think the quoted price to make one then was $25,000.

[bighonkintuba]

Here's one:
http://www.ebay.com/itm/Hirsbrunner-3V- ... 3ce7966f2e" target="_blank

[Jose the tuba player]

Here's one:
http://www.ebay.com/itm/Hirsbrunner-3V- ... 3ce7966f2e" target="_blank

I know its been up a few times before, does anyone know if this a good tuba? i played a Yamaha 3+1 compensator and i thought it sucked, would these be better?

[iiipopes]

Here's one:
http://www.ebay.com/itm/Hirsbrunner-3V- ... 3ce7966f2e" target="_blank" target="_blank

I know its been up a few times before, does anyone know if this a good tuba? i played a Yamaha 3+1 compensator and i thought it sucked, would these be better?

The search engine is your friend:
viewtopic.php?f=2&t=58333&p=491380&hili ... ng#p491380" target="_blank
viewtopic.php?f=2&t=48989&p=422633&hili ... ng#p422633" target="_blank

[Jose the tuba player]

Here's one:
http://www.ebay.com/itm/Hirsbrunner-3V- ... 3ce7966f2e" target="_blank

I know its been up a few times before, does anyone know if this a good tuba? i played a Yamaha 3+1 compensator and i thought it sucked, would these be better?

The search engine is your friend:
viewtopic.php?f=2&t=58333&p=491380&hili ... ng#p491380" target="_blank
viewtopic.php?f=2&t=48989&p=422633&hili ... ng#p422633" target="_blank

I have already seen these i was wondering if there were more people who have played these, or are these tubas not common?

[Lars Trawen]

Gronitz in Hamburg does now have a pure double tuba in F and BBb.
It's a better choice than a compensator.
http://www.gronitztuba.de/index.php?id=16

[imperialbari]

Very interesting link, Lars!

They should have been more generous with the specifications. The fourth valve of the. BBb side could be an interesting weight saving aspect. My guess is that is a full step up into a CC bugle. The low B natural then would be fingered 24 on the BBb side.

Klaus

[J.c. Sherman]

As proven by rotary piccolo trumpets, there's no painful limitation on short slide length from rotors any more than pistons.

There are many double compensating or 3v compensating tubas with rotors out there, and they are much easier to make than full doubles. They are, however, more resistant than many full-double designs.

J.c.S.