Can someone explain, in acoustics terms, why a tin whistle is overblown with more pressure to get to the next octave while a recorder uses a thumbhole? I mean, they’re both duct flutes so I cannot fathom why venting an extra hole just gives you another note on the tin whistle (e.g. nat C) but changes the waves in such a way that the next octave is reached on the recorder.
I know that opening more holes shortens the effective length of the tube so why is it that on the tin whistle putting a thumbhole at the back can give you access to a natural C (with the right diameter of course) but on the recorder gives you access to the next octave.
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It’s all about the location of the thumbhole.
To get a C natural on a D tin whistle, the thumbhole will lie between the 1st and 2nd finger holes. (But on the back of the whistle, where the thumb lives.)
But on the recorder, the thumbhole lies above the 1st finger hole. It’s job is to make the lower octave unviable, so the lowest viable note is the second octave. And the thumbhole is mostly played only partly open.
Hope that’s enough information, but come back to us if it doesn’t answer your questions.
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Thanks Terry. That makes sense. So it’s really just the placement? Does the size of mouthpiece play into this or affects other aspects of the sound? Recorders seem to have much larger mouthpieces compared to tin whistles (or at least relative to the bore at the finger holes).
If we’re talking about the mature Baroque recorder, music written for it typically goes into the third octave (occasionally by a perfect fifth). This developed hand-in with a bore that acquired a considerably more complex profile than the tin whistle has.
Both overblow in response to an increase in breath pressure, but the recorder thumbhole provides an alternative “speaker device” with considerably greater flexibility and agility. It also minimizes the increase in volume in successively higher registers.
The width of the window as a fraction of bore diameter at the window, is a carefully scaled dimension of labial pipes on organs. It could probably be applied to the categorization of duct flutes of the type we’re talking but I wouldn’t assume that it clusters significantly differently on recorders and tin whistles.
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I don’t think it’s all about that, although higher up is more convenient. On a whitle you can do the same thing by partially opening the top hole, but it also works with any of the other holes above the lowest one that needs to be held closed, so play any first octave note and then slightly open any of the holes above it to jump up an octave. The advantage of using the highest hole for this venting is that you can use the same one for all the second octave notes up until you reach the highest second octave notes at which point they go sharp. Ideally the hole would be a lot further up, but you’d need to fit a key with a long rod to reach it.
The biggest difference with the recorder is that the windway is positioned in a way that makes it harder to go up an octave by overblowing so as to make the first octave notes maximally strong, forcing venting to be used as the best way of producing second octave notes. It’s advantageous to use the thumb for venting to take it a little bit further up and have high second octave notes play less sharp, but there’s no reason why a whistle shouldn’t have that too, and indeed the ones I make do have that because they’re built as quenas with whistle converters to hold a windway in the right place. They have a thumb hole that’s used to aid the formation of third octave notes, but it also provides an alternative fingering for the first note of the second octave. That thumb hole can also be used for venting to play second octave notes, but the cost of venting is that there’s a bit of hiss with every note that’s out of tune with the main note being played, whereas if you overblow instead you get hiss that’s in tune with it. It’s good to have more options as to how to play any specific note. The downside of a thumb hole is that condensation can run out of it unless you build a structure in the bore to steer it past the hole.
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