I have a vintage Wylde 8-key flute.
Took me awhile to get used to the embouchure, but after a few months I was finally able to get a sizzling low D… that is, in my first 10 minutes of playing. Then the low D just starts to fade into the upper octave entirely. Haven’t had this issue with any other flutes.
Has anyone experienced this? Is there any sort of mechanical reason that a flute would start leaking after being warmed up? Or is my tiring embouchure for sure to blame here?
Cracks normally seal a bit after warming up the flute. Have you tried the “suck” test on each section? That’s the first thing to try. You may just be wearing out a bit, but there could be a leak somewhere or your fingers are partially opening a key by mistake.
Eric
It could be a crack in a socket that starts to open as the tenon expands.
It could also be an issue with keys that have a bit of play in them. Sometimes you can have a key like this that seals fine, but if you bump the key touch with your finger accidentally, it can move the key pad sideways a bit and allow the key to settle in a position that now allows it to leak air. One way to test for this kind of thing is to take off all the keys, seal their holes with blu tack and see if the problem continues to occur.