OK, OK, I was being a bit extreme in my wood thicknesses and metal weights, although a few very large-scale theatre organ ranks certainly can have dimensions in that ball park. It isn't typical in the classical organ field.tuben wrote:I totally disagree. In my years as an organbuilder, I can count on one hand the number of times I've encountered a wooden pipe with anywhere near the thickness of lumber you talk about. And those were for 32' stops, not 16'. <...SNIP...>Different types of organ pipes have different proportions of fundamental to harmonics. An organ builder who wants to build a 16' C pipe that will have plenty of fundamental will use several hundred pounds of lead to make the pipe, or will make it of wood at least two inches thick.
Still, my point was that, if you want to produce a low frequency, you need a resonator that can hold in that frequency, that is, a resonator that does not itself vibrate at that frequency, letting the low frequency leak out instead of confining it inside the tube. A thin brass walled resonator, such as a tuba, allows the low frequencies to pass out directly through the tubing wall, and there is no effective resonator for the low frequency. The thin brass does a fine job of keeping in the harmonics, so the tuba does a good job of producing those.
There was a topic a little earlier that had posts about enjoying the tuba vibrating in one's arms. I enjoy it too. However, I know that if I ever had a tuba that could produce a real fundamental pedal tone, it would not vibrate in my arms: all of the energy in the horn would go into producing a low frequency out of the bell, not in vibrating the walls of the horn.
Cheers,
Allen