Acoustics of baroque, classical and modern flutes

modern flute
B foot

C#5

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

Impedance

Fingering
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 C#5. Z is plotted in dB, i.e. 20 log(Z/Pa.s.m-3).

From E4 to C#5 and E5 to C#6, each standard fingering serves for two notes. The flutist uses the same fingering for C#5 and C#6, but changes the speed, length and shape of the jet. The first three minima can be played. This note is acoustically different from others in the first register because the highest tone hole opened is smaller than the other tone holes (not counting the two trill/register keys). This is because it also serves as a register hole for D5, D#5, D6 and A6. The latter use largely determines its position, and its size is chosen to tune C#. The acoustic difference in this note is enhanced by it being the last note below the change in register: compare the impedance spectrum with that for D5.

Sound


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

Sound Clip

You can hear C#5 played by Geoffrey Collins.

Alternative Fingering

modern flute B foot

Impedance


Fingering
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 alternative fingering for C#5.

Comparing with the standard fingering, one sees that the effect of closing a hole downstream from 10 open holes is very small at frequencies below the tone-hole filtering limit of about 2.5 kHz, but that there are discernible differences at higher frequencies.


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.