Posted by Rick Denney on February 09, 2003 at 19:05:48:
In Reply to: Re: Re: "double" tubas posted by JoeS on February 09, 2003 at 18:27:38:
The only difference between a double tuba as described by Mr. Coulter (and by Barry G) and the one you describe is that in your instrument, the CC valves are operated by different buttons. On a double tuba as they describe, the same buttons are used to operate whole-step, half-step, and 1.5-step valves, no matter whether the instrument is operated in F or CC. So, perhaps it's really the difference between an automatic double instrument versus a manual double instrument, just as the Blaikley system is an automatic compensation system versus a tuning stick, which is a manual compensation system.
What you describe is a regular instrument with valve lengths needed for both instruments in line, plus a change loop. It has the same disadvantage as the "double" instrument, in that the CC side uses a longer percentage of straight tubing compared to the F side, though the CC valve branches can (in both cases) use a larger bore or even a graduated bore. A single-pitch CC would have a much less straight tubing. The advantage of the six-valve instrument is that the valves have the normal number of ports and are light. The advantage to the "automatic double" is that the valves mean the same things in both pitch systems, so they don't require nearly as much of a shift in technique for the player familiar with both single-pitched tubas. With the automatic double, you can think of of the tuba as an F routinely, or as a C when needed, and use the same buttons you always do. With the six-valve tuba, I don't expect most think of the buttons in terms of a double tuba, but rather they memorize the valve combinations needed to achieve the best results in the low register. Thus, an automatic double is so because it operates like a double.
The problem of too much cylindrical tubing isn't really a problem, I don't expect. As Barry describes, the point of having a F/CC double is to simplify the fingerings in the low register, not to create a standalone CC tuba and a standalone F tuba in the same package. The CC side should have a sound that corresponds in the low register with the F side to achieve this objective. That is much easier than achieve a good CC sound in all registers, as would be required of a single-pitch CC tuba.
Rick "who sees no need for this to be an emotional subject" Denney