Markus Schneider - FH-Regensburg

Acoustics of the Acoustics of the CajonCajon

ContentContent

HistoryHistory Acoustic System of the Cajon – Acoustic System of the Cajon –

OverviewOverview PlatePlate Helmholtz ResonatorHelmholtz Resonator Other ResonatorsOther Resonators EquipmentEquipment

HistoryHistory

Origin in PeruOrigin in Peru The first instruments were shipping The first instruments were shipping

boxesboxes ““Cajon” is the Spanish word for boxCajon” is the Spanish word for box Adopted by Cuban flamenco Adopted by Cuban flamenco

percussionistspercussionists

Acoustic System - Acoustic System - OverviewOverview

Coupled System

Helmholtz

Resonator

Plate with

clamped edges

Plates – Modes of Plates – Modes of vibration 1vibration 1

TheoryTheory SimulationSimulation Recorded Recorded VideoVideo

FundamentalMode

(0,1) Mode

Plates – Modes of Plates – Modes of vibration 2vibration 2

TheoryTheory SimulationSimulation Recorded Recorded VideoVideo

FundamentalMode

(1,0) Mode

Helmholtz-ResonatorHelmholtz-ResonatorCalculationCalculation FFTFFT

C: Speed of waves in airr: Radius of the holeV: Volume of the body

Dominant frequency : 160 Hz

Other Helmholtz Other Helmholtz ResonatorsResonators

Exhaust systemExhaust system LoudspeakerLoudspeaker Body of other Body of other

musical instrumentsmusical instruments

EquipmentEquipment

Acoustic Camera Acoustic Camera 33 microphones “make sound 33 microphones “make sound visible”visible”

Software Software NoiseImage NoiseImage

Equipment can be Equipment can be seen at FH-Regensburgseen at FH-Regensburg Mechanical Mechanical

EngineeringEngineering

Markus Schneider - Acoustics of the Cajon

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