Acoustics of the clarinet

Bb clarinet

C#5

Music Acoustics UNSW

index
E3 F3 F#3 G3 G#3 A3 A#3 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

Impedance

Fingering
a key depressed
a key not depressed
a hole covered
a hole uncovered
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 clarinet acoustics

Notes are the written pitch.
Frequencies are the sounding frequency, for Bb clarinet.
Unless otherwise stated, the impedance spectrum is for a Bb clarinet.


Impedance spectrum of a Bb clarinet measured using fingering for C#5.

Note how similar this spectrum is to that for F#3. (Of course, the clarinet overblows a 12th.) The only substantial difference is the reduction in the first peak. The purpose of the speaker key is just that: to destroy the fundamental resonance so that the instrument will not 'drop down' to the lower register. See register hole for details.

At frequencies below about 1.1 kHz, this curve looks rather like that for B4 or C5, but raised in frequency because the tube is effectively shorter because of the open tone holes. At higher frequencies, however, the waves propagate past the open tone holes with greater ease, and the situation is more complicated, which gives rise to the irregular shape around 1.2 kHz. (See cut-off frequencies.)

For a general discussion of the clarino register, see the description on B4.

Sound


Sound spectrum of a Bb clarinet played using fingering for C#5.
For more explanation, see Introduction to clarinet acoustics

Sound Clip

You can hear C#5 played.


Fingering legend
How were these results obtained?

Contact: Joe Wolfe / J.Wolfe@unsw.edu.au
phone 61-2-9385-4954 (UT +10, +11 Oct-Mar)
© 1997-2006 Music Acoustics UNSW