Introduction to Acoustics

Concert Hall Acoustics Based on Subjective Preference Theory 10.3 Individual Preferences of a Listener and a Performer 371
introduced at the Kirishima International Concert Hall in
1994. The sound simulation system employed multiple
loudspeakers. It used arrows for testing the subjective
preference of four listeners at the same time. Since the
four orthogonal factors of the sound field influence the
a)
b)
S2
1
–3
–1.5
c) S3
1
0
–1
–2
–3
–1.69
d)
S1
1
0
–1
–2
–3
70
0
–1
–2
S4
1
0
–1
–2
–3
0
75
–0.8
–1.01
80 85 90
Listening level (dBA)
–0.07 0.62 1.32
log Ät1/[Ät1]p
–0.31 –0.38 1.07
log Tsub/[Tsub]p
0.4 0.75
1
IACC
83dBA
26.8ms
2.05s
Fig. 10.26a–d Scale values of preference obtained by
paired-comparison tests for the four orthogonal factors,
subject BL. (a) The most preferred listening level was
83 dBA, the individual weighting coefficient in (10.9):
α1 = 0.06; (b) the preferred initial time delay gap between
the direct sound and first reflection was 26.8 ms, the individual
weighting coefficient in (10.9): α2 = 1.86, where [∆t1]p
calculated by (10.4) with (τe)min =62 ms for the music used
(A = 4) is 24.8ms;(c) the preferred subsequent reverberation
time is 2.05 s, the individual weighting coefficient in
(10.9): α3 = 1.46, where [Tsub]p calculated by (10.6) with
(τe)min =62 ms for the music used, is 1.43 s; (d) individual
weighting coefficient in (10.9) forIACC: α4 = 1.96.
preference judgment almost independently [10.1], each
single factor is varied, while the other three are fixed at
the preferred condition for the average listener. Results
of testing acousticians who participated in the International
Symposium on Music and Concert Hall Acoustics
(MCHA95), which was held in Kirishima in May 1995,
are presented here [10.1].
Individual Preference and Seat Selection
The music source was orchestral, the Water Music
by Händel; the effective duration of the ACF was
62 ms [10.11]. The total number of listeners participating
was 106. Typical examples of the test results
for listener BL as a function of each factor are shown
in Fig. 10.26. Scale values of this listener were rather
close to the averages for subjects previously collected:
the most preferred [LL]p was 83 dBA, the value
Stage
Fig. 10.27 Preferred seating area calculated for subject BL.
The seats are classified in three parts according to the scale
value of subjective preference calculated by the summation
of S1–S4 (10.8) together with (10.9). Black indicates
preferred seating areas, about one third of all seats in this
concert hall, for subject BL
Part C 10.3