Acoustics of baroque, classical and modern flutes

modern flute
B foot

C#5 & E6

Music Acoustics UNSW

modern B modern C classical C classical D classical flared baroque B3 B3
C4 C#4 D4 D#4 E4 F4 F#4 G4 G#4 A4 A#4 B4
C5 C#5 D5 D#5 E5 F5 F#5 G5 G#5 A5 A#5 B5
C6 C#6 D6 D#6 E6 F6 F#6 G6 G#6 A6 A#6 B6
C7 C#7 D7 D#7 E7 F7 F#7 multiphonics


a key depressed
a key not depressed
a part of the mechanism that is not normally touched
Details in fingering legend.

Acoustic schematic
a closed tone hole
an open tone hole

Non-specialist introduction to acoustic impedance
Non-specialist introduction to flute acoustics

Impedance spectrum of a modern flute with a B foot measured at the embouchure hole using fingering for the multiphonic C#5 with E6. Z is plotted in dB, i.e. 20 log(Z/Pa.s.m-3).

This may be compared with the fingering for A4, but with a register hole to play E6. It may also be considered as the trill fingering for D5 (C5 to D5 / C#5 to D5) with enough cross fingering to flatten it approximately a quarter tone. The 3rd and 1st minima, respectively, correspond to these pitches.

For this situation to apply, the frequencies of the notes have to be such that the effect of the inertia of the air in the open tone hole is large enough to allow some transmission past the hole, but small enough to produce some reflection. For low-pitched notes, the tone hole is usually small.


Sound spectrum of a modern flute with a B foot played using fingering for the multiphonic C#5 with E6.

Sound Clip

You can hear the multiphonic C#5 with E6 played by Geoffrey Collins.

The Virtual Boehm Flute may suggest other fingerings for this multiphonic.
Fingering legend
How were these results obtained?
Acoustic measurements are available for these flutes -
modern B, modern C, classical C, classical D, classical flared, baroque
Sound clips are available for modern B, classical flared and baroque
To compare flutes, it is easiest to open a separate browser window for each instrument.

Copyright © Academic Press. JSV+ Joe Wolfe, John Smith, John Tann and Neville H. Fletcher, Acoustics of baroque, classical and modern flutes
Revised to include the baroque flute 2001.