일전에 Reverberation Time 측정하는 법을 적어두었던 것이 있어서 올립니다.
[procedure]
1. Signal generation : choose one below.
(1) frequency modulated sine signal (100-5000Hz)
(2) random noise
(3) pure sinusoidal tones
(4) pistol shot
2. Omni-directional microphone is used to record a sound.
3. Distance between the sound source and microphone is much larger than reverberation distance.
cf. reverberation distance r
V is a room volume.
A = alpha*S , where alpha is absorption coefficient and S is size of room
4. Draw a logarithmic level decay curve
5. approximate it to a straight line by least square fitting or just visually doing.
6. Calculate reverberation time using following equation
[Theoretical Reverberation Time Calculation]
T=0.163*V/A [sec]
V : room volume , A=alpha*S
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