Flute acoustics: measurement, modelling and design - School of ...

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Contents
Dedication ...............................................
Acknowledgements ..........................................
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v
Abstract ................................................ vii
CHAPTERS
I Introduction ............................................ 1
1.1 Introduction to flute acoustics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 The flute maker, the curator and the software engineer . . . . . . . . . . . . . . . . . . 2
1.3 ‘FluteCAD’: taking the guesswork out of flute design . . . . . . . . . . . . . . . . . . . . 3
1.4 How flutes work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.5 Acoustic impedance: predicting the playing qualities of a flute . . . . . . . . . . . . . . 6
1.6 Tuning, tradition and the ‘standard flutist’ . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.7 Software implementation: goals and limitations . . . . . . . . . . . . . . . . . . . . . . . 8
1.8 Guide to the thesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
II Theory and literature review .................................. 11
2.1 Flutes and flute making . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2 Acoustics of woodwind instruments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.3 Computer models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
III Measuring acoustic impedance ................................ 31
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
3.2 Review of measurement techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.3 Theory of acoustic impedance measurements . . . . . . . . . . . . . . . . . . . . . . . 32
3.4 Calibration of impedance heads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
3.5 Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.6 Optimisation of the output signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
3.7 Materials and methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
3.8 Results and discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
IV Finger hole impedance spectra and length corrections .................. 53
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.2 Materials and methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
4.3 Results and discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59