Transcript Acoustics of the Cajon Markus Schneider - FH-Regensburg

Acoustics of the Cajon
Markus Schneider - FH-Regensburg
Content
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History
Acoustic System of the Cajon – Overview
Plate
Helmholtz Resonator
Other Resonators
Equipment
History
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Origin in Peru
The first instruments were shipping boxes
“Cajon” is the Spanish word for box
Adopted by Cuban flamenco percussionists
Acoustic System - Overview
Coupled
System
Plate with
clamped
edges
Helmholtz
Resonator
Plates – Modes of vibration 1
Theory
Fundamental
Mode
(0,1) Mode
Simulation
Recorded Video
Plates – Modes of vibration 2
Theory
Fundamental
Mode
(1,0) Mode
Simulation
Recorded Video
Helmholtz-Resonator
Calculation
FFT
C: Speed of waves in air
r: Radius of the hole
V: Volume of the body
Dominant frequency : 160 Hz
Other Helmholtz Resonators
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Exhaust system
Loudspeaker
Body of other
musical instruments
Equipment
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Acoustic Camera
 33 microphones “make sound visible”
Software
 NoiseImage
Equipment can be
seen at FH-Regensburg
 Mechanical
Engineering
Thank you for your attention!
Markus Schneider - Acoustics of the
Cajon