Page 257 - The Master Handbook Of Acoustics

232 CHAPTER NINE

and 23 or 24 ft long might use 20 modules of distributed types, four
modules high and five long. It is good practice to have acoustically
dissimilar modules opposing each other on opposite walls.
The question that comes to mind is, “How about diffusion of sound
with such modular treatment?” BBC experience has shown that care-
ful distribution of the different types of modules results in adequate
diffusion.

Endnotes

1
Young, Robert W., Sabine Reverberation and Sound Power Calculations, J. Acous. Soc. Am.,
31, 7 (July 1959) 912–921. See also by the same author, On Naming Reverberation Equations,
31, 12 (Dec 1959) 1681.
2
Gilford, Christofer, Acoustics for Radio and Television Studios, London, Peter Peregrinus,
Ltd. (1972), Chapter 8.
3
Anon., Noise Control Manual, Owens-Corning Fiberglas Corp. (1980), publication No. 5-
BMG-8277-A.
4
Sonex is manufactured by Illbruck USA, 3600 Washington Ave., North, Minneapolis, MN
55412.
5
Harris, Cyril M., Acoustical Properties of Carpet, J. Acous. Soc. Am., 27, 6 (Nov 1955)
1077–1082.
6
Anon., Acoustical Ceilings: Use and Practice, Published by the Ceiling and Interior Systems
Contractors Association (1978). See Appendix.
7
Schultz, Theodore J. and B. G. Watters, Propagation of Sound Across Audience Seating, J.
Acous. Soc. Am. 36, 5 (May 1964) 885–896.
8
Rettinger, Michael, Bass Traps, Recording Eng./Prod., 11, 4 (Aug 1980) 46–51.
9
Mankovsky, V. S., Acoustics of Studios and Auditoria, London, Focal Press, Ltd., (1971).
10
Siekman, William, private communication. (Mr. Seikman was manager of Riverbank
Acoustical Laboratories at time of these measurements, which were reported to the Acous.
Soc. Am. April 1969.)
11
Brüel, Per V., Sound Insulation and Room Acoustics, London, Chapman and Hall (1951).
12
Callaway, D. B. and L. G. Ramer, The Use of Perforated Facings in Designing Low-
Frequency Resonant Absorbers, J. Acous. Soc. Am., 24, 3 (May 1952), 309–312.
13
Ingard, U. and R. H. Bolt, Absorption Characteristics of Acoustic Materials with Perforated
Facings, J. Acous. Soc. Am., 23, 5 (Sept 1951), 533–540.
14
Davern, W. A., Perforated Facings Backed with Porous Materials as Sound Absorbers—An
Experimental Study, Applied Acoustics, 10 (1977), 85–112.
15
Rettinger, Michael, Low Frequency Sound Absorbers, db the Sound Engineering Magazine,
4, 4 (April 1970), 44–46.