Why does a dronereed (after scraping) sometimes have a double tone (tone jumps when pressure rises).
Is there a cure?
Wild guess?..the mode of vibration alters…cure?..maybe weight the tongue
till the double tone is a definite switch as pressure increases. Else, the heel of the shoe
is especially effective in curing a drone reed of instability (amongst other things).
Actually, its desirable when its in the right way…listen to Ennis starting his
drones, particularly on the “Wandering Minstrel”…hear the kind of of unstable
wavering for half a second before the pressure puts the drone into a very stable, slightly
lower pitch mode. Once you experience this for yourself, you’ll not forget it.
Completely different from a weak drone that just wanders all over the place endlessly.
M
I have an elder drone reed that is 87mm long, from base end to tip of tongue, the tube is 5.5mm wide, and wall thickness is about 1.5mm. If I draw with a certain deep soft breath it will produce an E4. If I draw with stronger breath it plays up a min3rd at G4. This must be because the distance is shortened from tip of tongue to the place where it’s freed up to vibrate. This distance probably changes more or less as you increase/decrease air pressure. E4 would be the total free distance of tongue vibration from where the split ends, and G4 would be the shorter distance as it lays flatter against the shoe–pressure shortens the distance. And that could be caused by the way the scrape is suddenly graduated, or a flaw in the wood. Just guessing though. I have other similar reeds that only produce one tone whether low or high pressure is applied.
See my video about overblown drone reeds on the NPU’s “Heart of the Instrument” DVD’s.