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me...??
I've been scratching my head with this gigantic 5-rotary B-flat tuba (many posts of mine regarding) - Miraphone model 98.
There IS a 4th slide "over there", but it's even MORE "way over there" than with the tubas described above the === line, and - simply - impractical.
OK...This tuba does offer "sousaphone quality" so-called false/privilege tones...so (mostly) I've been playing that pitch with 3rd valve, and it's - well... - "fine", but I would also like to have the "real" valve combination (5-2-3-4) be usable (rather than 20 c. sharp) as well...
...I finally came up with a not-terribly-difficult-to-fabricate and FAR-EASIER-to-execute solution.
Take a look at the looped-over #5 slide (right next to the #1 slide (the #1 of which I just sank down lower by c. 5/8" for second-space/line C/B intonation considerations.
If I have Miraphone send me another rotor, a bit more (I've already bought some) inside/outside 21.2" bore nickel slide tubing, and (already have) a #2 slide bow, I can take advantage of my left hand ALREADY being in that position, and push a spring-loaded trigger activating (sure...) a 6th "dependent" rotor to lengthen the #5 slide - which will render the 5234 "double low" C as dead on.
Often (if not usually) adding a special feature such as this defines discovering addition uses for it, but - at this time - I can't imagine what those would be...
anyway...
![Image](https://i.imgur.com/wHe98Jr.jpg)