F#7 and G7 on the Boehm flute

F#7 B foot

Th     3   | 1   3 D# C# 
Th 1   3   | 1   3 D# C#
Th 1   3   | 1   3 D# C# gizmo

 F#7 C foot
 

Th     3   | 1   3 D# C

 G7 B foot
 

Th   2 3    |   2   tr1 C B

 G7 C foot
 

Th   2 3 G# |   2

Our resident flutist, Jane Cavanagh, can play these notes for short durations, but they are of limited musical use.

There is simple acoustical reasons why the flute does not have helpful resonances in the upper half of its fourth octave. In this frequency range, the acoustic impedance of the volume of air between the cork and the embouchure hole dominates the effects of the main bore. (See flute acoustics.) If you look at any of the theoretical or measured impedance curves, you will see that the curves have little structure in the range 3 to 4 kHz. It is possible to shift this effect of the upstream air to higher frequencies by moving the cork closer to the embouchure hole. This does allow you to play higher notes, but it has highly undesirable consequences on the internal tuning of the instrument. The fingerings given above were predicted and played with the normal cork position, 17.5 mm beyond the centre of the blow hole.