Benchmark Problems for Acoustical Parameters

Actual Room: C-11

Find values of reverberation time (T), early decay time (EDT), clarity (C₈₀) and center time (T_s) from following impulse response.

c11.wav (RIFF waveform, 16 bit signed integer, monoral, sampling frequency: 48000 Hz)
c11.fb (floating-point binary (little endian), 131072 data, monoral, sampling frequency: 48000 Hz)

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Note

This impulse response is measured in a concert hall of which having about 500 capacity seats and is done under unoccupied condition.

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Reverberation Time: T (s)

	125	250	500	1k	2k	4k	Regression interval
Okubo	1.80	1.66	1.72	1.94	1.98	1.72	-5 ~ -35 dB (T30)
Yasuda	1.80	1.69	1.75	1.98	2.01	1.74	-5 ~ -35 dB (T30)
Miyazaki	1.79	1.66	1.72	1.94	1.98	1.70	-5 ~ -35 dB (T30)
Yairi	1.75	1.67	1.73	1.93	1.94	1.76	-5 ~ -35 dB (T30)

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Early decay time: EDT (s)

	125	250	500	1k	2k	4k
Okubo	1.63	1.93	1.96	1.93	2.11	1.72
Yasuda	1.63	1.95	1.87	1.94	2.13	1.73
Miyazaki	1.58	1.90	1.86	1.90	2.12	1.67
Yairi	1.64	1.82	1.87	2.01	2.03	1.68

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Clarity: C₈₀ (dB)

	125	250	500	1k	2k	4k
Yasuda	-1.52	-2.93	-1.29	-0.59	-1.98	-1.48
Hoshi	-1.47	-3.01	-1.31	-0.60	-1.96	-1.49
Miyazaki	-1.18	-3.06	-1.22	-0.61	-1.90	-1.49

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Center time: T_s (s)

	125	250	500	1k	2k	4k
Hoshi	0.131	0.158	0.140	0.138	0.155	0.136
Miyazaki	0.139	0.160	0.137	0.133	0.153	0.134