04/11/2014
Norwegian Acoustical Society, Autumn Meeting 2014, Gardermoen
Flute acoustics
Jens Holger Rindel Multiconsult 2014-10-24
Outline
• Origins of flutes • Acoustic principles • Flutes with closed tube • Vessel (cavity) flutes • Overtone flutes • Vertical flutes • Fipple flutes (recorders) • Transverse flutes
1 04/11/2014
The Jiahu gǔdí (贾湖骨笛 ) is the oldest known musical instrument from China, dating back to around 6000 BC. Gudi literally means "bone flute".
Sound generation
Air stream against a sharp edge, Coltman, 1968
2 04/11/2014
Acoustical principles of flutes
• Cavity flutes
• Closed tube
• Open tube
Open and closed tubes Lowest resonances (harmonics)
3 04/11/2014
Open and closed tubes Lowest resonances (harmonics)
Open – relative frequencies: 2 – 4 – 6 – 8 – 10 - 12
Closed – relative frequencies: 1 – 3 – 5 – 7 – 9 - 11
Selje-fløyten (Norwegian willow flute, combining open and closed harmonics)
Chr. Skredsvig 1889
4 04/11/2014
Tone holes
1
1: Marno flute (Denmark) for demonstrating principles
5 04/11/2014
2 3
4
Flutes with closed tube 2: Pan flute, 3: Wiking pan flute (York, ca. 1000 AD), 4: Swanee flute
5
Organ pipe, closed type
6 04/11/2014
8 6 7
10 11 9
Vessel (cavity) flutes 6: Ancient (China), 7: Boatman’s whistle, 8: Nightingale whistle (Turkey) 9: Medieval (Wismar, Germany) 10: Modern clay flute (Austria) 11: Gemshorn (Germany)
12
13
Overtone flutes 12: Willow flute (Selje fløyte, Norway) 13: Txistu (Basque)
7 04/11/2014
14
Overtone flute 14: Fujara (Slovakia)
15
16
17
Vertical flutes 15: Bamboo flute (Africa) 16: Shakuhachi (Japan) 17: Tung Xiao (China)
8 04/11/2014
18
Fipple flute 18: Folk music instrument (Slovakia) - Front and back
19
Fipple flute 19: Penny whistle (Ireland)
9 04/11/2014
20
21
22
Recorders (Baroque style) 20: Alto 21: Soprano 22: Sopranino
23
24
Transverse flutes (cylindrical bore) 23: Bamboo flute (Japan) 24; Military Fife (USA)
10 04/11/2014
25
Transverse flute 25: Dizi (China) – with resonating membrane of rice paper
Transverse flutes (wood, conical bore) 26: Baroque traverso 27: six keys flute 28: nine keys flute 29: Boehm ring key flute (1832) 30: Modern piccolo
26
27
28
29
30
11 04/11/2014
31
32
Modern transverse flutes (silver, cylindrical bore) 31: Normal flute 32: Alto flute (G-flute)
12