声学基本概念 - 图文 

Diffusion of Sound

b<< λb >> λbbExample :b = 0.1 m

λ = 0.344 m (≈ f = 1 kHz)

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Example:b = 0.5 m

λ = 0.344 m (≈ f = 1 kHz)

Reflection of Sound

SourceSourceSourceImaginary Source

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Sound Frequencies

Infra

Audio

Ultra

0.020.2220200200020.000200KHzFrequency

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Auditory Field

140dB120100Sound Pressure Level80604020020

Thresholdin Quiet50

100

200

5001k2kFrequency [Hz]

5k

10k

20 k

MusicSpeechThreshold of PainLimit of Damage RiskBA 7666-11, 39

960423

Equal Loudness Contours for Pure Tones

120

130120110100908070605040302010Phon20 Hz

100 Hz

1 kHz

Frequency

10 kHz

Soundpressurelevel, Lp

(dB re 20 μPa)

100806040200

BA 7666-11, 40

970379