Page 230 - Master Handbook of Acoustics

FIGURE 11-15 Spaces designed for speech and music recording require short reverberation times.

Reverberation chambers, which are used for measuring absorption coefficients, are carefully
designed for the longest practical RT to achieve the maximum accuracy. In this unique application,
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the optimum reverberation time is the maximum attainable.
The best reverberation time for a space in which music is played depends on the size of the space

and the type of music. No single optimum universally fits all types of music; the best that can be done
is to establish a range based on subjective judgment. For example, slow, solemn, melodic music, such
as some organ music, is best served by long reverberation time. Quick rhythmic music requires a
shorter reverberation time from chamber music.

The reverberation times for churches in Fig. 11-13 range from the highly reverberant conditions
favored in liturgical churches and cathedrals in the upper area, to the shorter reverberation times of
more sermon-oriented churches in the lower area. Churches generally represent a compromise
between music and speech.
Figure 11-14 represents the range of recommended reverberation times for different concert halls.
Symphonic music is near the top and lighter music somewhat lower. The lower area applies for opera

and chamber music.
Recording studios present still other problems that do not conform to simple rules. Multitrack
recording in which musical instruments are recorded on separate tracks for later mixdown generally