Posted by Mark in Ohio on November 20, 2000 at 09:56:55:
In Reply to: How about a 3 rotor + 1 thumb rotor 4th? posted by James Soh on November 19, 2000 at 10:22:21:
Funny you shoul mention it!:
I've been looking into this for my Conn 12J.
The 12J is 3 valve, while the 4 valve 5J is arguably a bit stuffy in the low register.
I have been planning to add a rotor down the line instead of a 4th piston so that I could maintain the nice playing of the horn, while opening-up the bottom stuff.
The false tones and pedal BBBb are real nice on the horn, so the potential is there for some good stuff from FF on down. As is, it's stuffy from GGb (2+3) on down to EE (1-2-3+ pull 1st waaaay out)
The taper of this horn is pretty gradual as well, so that one has a couple places where the rotor could fit before the bore gets too large. there's a straight section well after the main slide that could take a .730 or .750 bore rotor, and after the next bow another straight section where one could put in an .8xx" bore rotor (probably overkill on this small of a horn).
These estimates are made by measuring outside taper w/ calipers, and subtracting estimated tube wall thickness to determine I.D. ("bore")
If I ever come up with the chump change to do the conversion, I'll post the results on this BBS. I like this little horn. I wanna like it a little more.
Is anyone out there an economical source for used rotary valves?
Mark "determined to bark out the low stuff on a 3/4 tuba" Mazak