Acoustics of baroque, classical and modern flutes

modern flute
C foot


Music Acoustics UNSW

modern B modern C classical C classical D classical flared baroque 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 C foot measured at the embouchure hole using fingering for G#4 and G#5. Z is plotted in dB, i.e. 20 log(Z/Pa.s.m-3).

The flutist uses the same fingering for G#4 and G#5, but changes the speed, length and shape of the jet. The first four minima can be played. These first five mimima support harmonics in G#4. In G#5, only the second and fourth minima are important. (Inaudible traces of the lower note are visible in the spectrum for G#5 which has tiny bumps at harmonics of G#4.) The acoustic diagram shows that there are two equivalent tone holes which, in principle, could each make the G-G# transition. Boehm's original key system ("open G#") did not have this inelegance, but he introduced this variation ("closed G#") because flutists were used to opening a hole with their LH fourth fingers. The two holes are rarely open at the same time.

The Virtual Boehm Flute may suggest other fingerings for this note.
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.