Does anyone know why the distance from the “sound hole” to the far end of the pipe is longer on a whistle than on a flute? I’ve made a couple flutes with separate whistle heads, and the length of the head (sound hole to end) is considerably longer on the whistle than on the flute.
My guess is that you’re not accounting for the cork position, which defines the end of the flute’s sounding length, whereas the fipple block defines the corresponding length of the whistle. And those ought to be very close, if you’re comparing like bores.
Overton Low D = 54 cm
Tipple D flute = 53.5 cm
A flute has a longer embouchure hole end correction than a whistle’s window end correction. Both have the same bottom end correction. These end corrections are added to the length of the bore to arrive at the total length of the vibrating air column. The total length of the vibrating air column determines the frequency of the root note. And it is longer than the bore length. A whistle’s window is usually bigger in area than the open gap you get between mouth and flute when blowing. This results in a shorter window/embouchure end correction for the whistle.
Whistles with smaller windows and/or higher walls around the window will have a higher end correction and consequently less bore length for a given base frequency. Likewise a personal flute embouchure will vary, and gets compensated with adjusting the slide. Different players may have the slide out to different degrees.
That also makes sense, Hans. Intuitively, a smaller/walled opening flattens the pitch, so you need to push in to compensate. Does that sound right?
Yes.
I am not sure about what you said about the cork position though. I thought that bit of extra space between embouchure hole and cork is there to help octave tuning, and the response of higher or lower notes. Does pushing the cork towards the embouchure hole result in increasing the pitch? I would not think it does.
See about cork position: http://www.phys.unsw.edu.au/jw/fluteacoustics.html#cork
(and the bit above about lipping).
yes, but it affects the 2nd octave much more than the first
Sure, primarily, that’s my understanding, too. So maybe this is a better way (for me) to think about it:
Let’s say that by sounding length I really mean (fudging a bit here) the entire bore chamber length that participates in the sound. And stipulate that the pitch is determined mostly by the position of the embouchure hole (flute) or fipple blade (whistle) with respect to the bell end. The upper distance from the hole/blade to the cork/block - call it X - is then primarily involved in end effects. And a longer X will tend to lower the pitch. Which partly compensates for shortening the pitch length when you move the hole further down the tube.
Now on a whistle, X is highly constrained by the window length to be very close to the block face which defines the chamber end, though it can be increased somewhat by undercutting the block (e.g. the cavity in Generations). Whereas X is less constrained on a flute, as the embouchure hole may be located at a range of distances X to give a more ideal result. So flute design principles will place the hole further down the bore, to account for the tighter embouchure, etc. But if you compare apples to apples, the total bore lengths will still be approximately the same (as seen in my measurements).
Of course, I’ve also seen flutes (my Chinese dizi is one) where the cork is adjacent to the embouchure hole, and actually overlaps the corresponding window position of a same-pitched whistle. But again the total bore lengths are about equal.
Does that make sense?
Hm, so it looks like the main difference (at least in mine) is the size of the emb hole/window, because it seems that even measuring from the cork/fipple to the end, it’s still a bit longer on the whistle than the flute.
Hmmm. I gather from th e OP that we are talking about instruments of the same internal diameter. If not that is another variable.