When tone holes are small relative to the bore, as for say recorder, then their size is quite relevant, affecting venting (hence pitch) a lot. A smaller hole lowers the pitch, even if the "northernmost" area of the hole's wall stays in the same location. After all, imagine if you reduced a normal size tone hole down to microscopic. It would stop acting as a tone hole at all.I've read up on how crescents work (on musicmedic.com) so I have a basic understanding of how tone hole placement affects pitch, but why would the tone hole sizes matter? If I move the top of the tone hole up the body 1mm how does that compare to enlarging the diameter 1mm? It would effectively do the same thing right? t.
However when tone holes are large relative to the bore, as with fltue or sax, the venting is already excellent, so enalrging the area has little effect.
But yes, if you increased the diameter by 2 mm, while leaving the location the same, that would be much the same as moving the tone hole 1 mm up the instrument. For the increased diameter, the slightly better venting might make the pitch slightly higher still.