Posted by Rick Denney on June 03, 2002 at 12:13:58:
In Reply to: The Engineered Tuba posted by Jim Andrada on June 02, 2002 at 21:13:24:
Before you can really define the engineered tuba, you have to define the requirements.
It is said that an engineer can do for a dollar what any fool can do for ten. The basis for that truism (whether or not you are prepared to believe it) is that engineers learn a process to achieve a successful design in an oderly way, minimizing turns down blind alleys. The first step in that process is to define the requirements. Once we have a clear understanding of the requirements, then we can create alternative designs, analyze them, select the best choices for the construction of prototypes, analyze the prototypes, and then go into production (assuming the dollars and cents work out).
For example, if the objective "durability" was high on the list, say above cost, then I might suggest several alternatives to current practices, including the use of materials that don't dent so easily. If the objective "intonation" were highest on the list, then the design would consider that at the expense of other objectives. Dr. Young's tuba is an example of a tuba that was designed based on a specific analytical objective. "Portability" was not high on his list of requirements, but it would be for most others.
A great example of an engineering improvement based on requirements is the fiberglass sousaphone. The requirements included light weight and durability for an instrument in a harsh, impact-prone environment, that would be cheap and look good despite abuse, and sound good enough for an outdoor parade or football-game show. Fiberglass sousaphones meet these objectives wonderfully, sounding acceptably good while being light and extremely durable in addition to being cheap.
Many of these requirements conflict with each other. For example, everyone loves 6/4 tubas because of their sound, but they all have intonation issues to one extent or another. The taper design that provides naturally good intonation may not be the same as the taper design that produces the sound everyone has in their heads. So the resulting tuba must be a compromise between these conflicting requirements. Analyzing these trade-offs quantitatively as would an engineer requires a quantitative understanding of these effects, which is quite difficult, and a quantitative assessment of their musical value, which may well be impossible.
If you are talking about using engineering techniques to construct tubas, then I suspect that these have been developed pretty well. Boosey and Hawkes and Yamaha use hydraulic presses that were engineered, and so on.
Of course, there are places where a little engineering common sense would go a long way. Rotary valve design is one such place, as we discussed in the other thread, where a little engineering could produce, fairly cheaply, rotary valves that could be renewed when they are worn without the high expense now required. Piston valves are a bit tougher. They work remarkably well considering the requirements for a nearly frictionless machine that seals effectively against air leakage, providing nearly full-diameter tubing switches that can still be operated by human hands. It is likely that the trial-and-error process of the last 180 years has arrived at solutions as close to optimal as would a good engineering process have achieved in much less time.
Where I think we could benefit from engineering the most is in carrying cases. The case I would design to really protect a tuba during transport is quite different from even the best cases currently available. My perfect case would suspend the bell flare in open air, for example, and would weight less than the tuba.
We might also benefit from good thinking about materials. For instruments made and repaired mostly by hand, brass is the ideal solution, being relatively cheap, plentiful, malleable, ductile, and strong. But a material that is much stronger might not need to be malleable, for example, because it would not dent and would therefore not need to be hammered. The composite bell on Daellenbach's Yamaha is an example. Fiberglass is another successful example, if you look at the requirements. We have talked before about constructing an aluminum tuba that is joined using epoxy glue instead of solder. But I think we'd need much more knowledge about the physics of tuba materials before we could analyze that choice, and it may well be cheaper to just build one and see what happens.
Rick "who has designed many complex systems, and who spends 60% of the time defining requirements" Denney