If John McClure is still not convinced. here's a simple test he can try
in his own garden. Take a 50-foot length of standard garden sprinkler
hose and blow down it, then take a 25-foot length of the same hose and
blow down that, and keep reducing the hose length until you're down to
1 foot.
Notice that, the shorter the hose, the easier it is to blow; the longer
the hose pipe the harder it is. Now, whether your blowing a small rank
of pipes or a full sized theatre organ, it doesn't matter: a long
delivery pipe causes drag which a short one doesn't.
A theatre organ capitalises on this effect with the tremulants: the
elastication of the wind in along small bore trunk greatly improves
the "bounce" effect, which of course, is so desirable.
Keep it short and good luck!
Paul Camps
[ Wierd and wonderful interaction may occur with long feeder pipes
[ when the pipe length supports resonance at or near the tremulant
[ frequency. For example, a 5-Hz tremulant frequency will resonate
[ at one-quarter wavelength in a pipe roughly 56 feet long (17 m),
[ or half-wave resonance at 112' (34 m). I don't know if the
[ tremulant can be adjusted with these coupled resonators; maybe
[ the pipe length must be increased to shift the resonance.
[ -- Robbie
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