UNSW - Science
News
Previous News Items
Good sax? Vocal tract control is key: research
By Dan Gaffney
February 8, 2008
Unlike amateurs, professional sax players can play notes in the very high altissimo sound register by tuning their vocal tract to assist the instrument, new research in the journal Science reveals.
The finding resolves a 25 year-old debate among scientists and players of reed instruments, such as the saxophone and clarinet.
It means that a player's vocal tract is sometimes more important than the instrument itself.
The longevity of the debate is due to the technical difficulty of making non-perturbing, precise, acoustical measurements inside the mouth during playing - that is, in a variable, humid environment with very high sound levels.
Australian scientists at the University of New South Wales demonstrated that professional players achieve this effect by systematically tuning their vocal tracts to resonate at a frequency close to that of the desired note. This tuning adds the tract's resonance to that of the saxophone, which allows the instrument to play above its normal range.
The research reveals that amateur players, who were unable to play notes in the altissimo range, did not tune a strong vocal tract resonance.
The standard range of the saxophone that is taught in elementary and intermediate stages of learning is a little over two and a half octaves. The altissimo range, used by experienced players, extends another octave or two above this.
"Acousticians have long debated whether and how the resonances of the vocal tract are involved in the playing of clarinet and saxophone," says Chen Jer-Ming, a UNSW PhD student. "We measured the resonances of saxophonists' vocal tracts directly, while they played. Over the standard range, there is no simple relation between tract resonances and notes played.
"However, in the altissimo range, the second resonance of the tracts of professional saxophonists was systematically tuned slightly above the desired note," says Mr Chen. "The players who couldn't achieve this effect were also those who couldn't play in the high range."
"Over the standard range, a resonance of the air within the saxophone determines the note played: you press the right keys and the right note (usually) comes out. But for the altissimo range, the sax's own resonances are weak, and to play up there you need to make the resonances of your own vocal tract stronger so they can assist those of the instrument to produce the desired note."
Although the effect was shown in the saxophone, similar effects are likely to be important in other single and double reed instruments, whose players also report the importance of the tract for special effects, including high register playing.
 |
 |
| Eminent sax player Col Loughnan of the Sydney Conservatorium of Music demonstrates the experimental apparatus. | Diagram of the experimental apparatus used for the analysis (see sound samples below). |
| In this sound file, a professional plays G4 and A#5 (written as A5 and C7 for the tenor saxophone). These are the notes used for Figs 1A and 1B in the scientific report of this study. | Loading... Play |
Download sound file (mp3) |
| An amateur plays G4 correctly. He then plays with the fingering for A#5. Because he does not tune the vocal tract resonance to A#5, the instrument plays at its strongest impedance peak, near 200 Hz, which is about G#3. | Loading... Play |
Download sound file (mp3) |
| A professional plays comfortably over the normal range (below about F5) and altissimo range of the tenor saxophone. The two passages cover the range D#3 to A#5 (written F4 to C7) and F3 to G5 (written G4 and A6). | Loading... Play |
Download sound file (mp3) |
| An amateur begins a scale at A#4 (written C6) near the top of the normal range. From F5 (written G6), he fingers the appropriate keys. However, without appropriate vocal tract tuning, the instrument plays at one of the lower impedance peaks. |
Loading... Play |
Download sound file (mp3) |
MEDIA CONTACT - DAN GAFFNEY, UNSW media, 0411 156 015