This is basically the same as the operation of the
Cessna Stall warning reed horn. On single engine Cessna
aircraft there is a double reed with an adjusting ring
in the leading edge of the wing. If the pressure gets
too low, i.e. too much lift (low pressure on top of
the leading edge) generated by a high angle of attack
air can be drawn through the reed making sort of a
honking noise. It is adjustable by a movable ring
on the reeds. The reed setup is only about $15.00.
I suspect that instead of in the leading edge a port
could be drilled in the side of the fuselage just above
the leading edge with the same results. I will buy
one and give it a try.jeff