Page 170 - The Master Handbook Of Acoustics
P. 170
145
REVERBERATION
0
125 Hz
10
63 Hz 250 Hz 500 Hz
20
30
Relative octave band level, dB 50 0.1 Sec
40
0
10
20 1 kHz 2 kHz 4 kHz 8 kHz
30
40
50
FIGURE 7-10
Decay of octave bands of noise in a small studio of volume 2,921 cu ft. Fluctuations due
to modal interference are greatest for low-frequency octaves containing fewer modes.
Reverberation Time
Variation with Position
There is enough variation of reverberation time from one position to
another in most rooms to justify taking measurements at several posi-
tions. The average then gives a better statistical picture of the behavior
of the sound field in the room. If the room is symmetrical, it might be
wise to spot all measuring points on one side of the room to increase
the effective coverage with a given effort.
