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Page 6
Projection Engineering, July, 1930
Why loudness
does not insure
good hearing
The volume of sound is largely contained in the lower frequencies of sound energy. But it is the upper frequencies which are the determining factor in the intelligibility of speech.
It is these upper frequencies that are most affected by a reverberant condition, resulting in the "fogging" of certain consonant sounds, even though normal in loudness.
Acousti-Celotex is a sound-absorbing tile, quickly and easily applied in new or old buildings. It is a permanent treatment. For it can be painted and repainted even with lead and oil paints without impairing its efficiency.
With Acousti-Celotex you can reduce the period of reverberation to the optimum figure.
Type BB Acousti-Celotex has a sound absorption coefficient of .70.
The necessary footage and the proper places for its application in each individual theatre can be accurately determined by the acoustical engineers of The Celotex Company. Submit your acoustical problems to them for study and recommendation — without charge or further obligation.
THE CELOTEX COMPANY
919 N. Michigan Ave., Chicago, Illinois
In Canada : Alexander Murray & Co., Ltd., Montreal. Sales
distributors throughout the World. Acousti-Celotex is sold
and installed by approved Acousti-Celotex contractors.
The word
CeilcdteX
(Reg. TJ. S. Pat. Off.)
is the trademark of and indicates manufacture by
The Celotex Company, Chicago, Illinois
Acousti Pelotex
FOR LESS NOISE-BETTER HEARING