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1945 Theatre Catalog, 4th Edition, Page 191 (169)

1945 Theatre Catalog, 4th Edition
1945 Theatre Catalog
1945 Theatre Catalog, 4th Edition, Page 191
Page 191

1945 Theatre Catalog, 4th Edition, Page 191

the suction ventilator by means of a thermostat placed in the return duct. This thermostat, working through a sys tem of compressed air, gradually opens or closes the swing dampers in a manner designed to keep an even temperature.

We might say, accordingly, that this air-conditioning system ftfeelsii the presence of the public and gives the audience a quantity of air in keeping with its size, for the increased temperature in the return duct causes the dampers to open wider, and a decrease in temperature caused by a smaller audience causes the adjuster to shut.


Another interesting experience during the construction of the Teresa had to do with acoustics. Despite the fact that the wall at the back of the theatre was covered with an acoustic absorption material boasting a 90 per cent absorption coefficient, a feeble echo was clearly discernible in the first few rows of seats, those nearest the screen. The owners postponed the imminent opening date until the echo could be eliminated.

All possible methods of avoiding the echo were tried, unsuccessfully, until at


last, through the cooperation of Guillermo Debus, manager of the Western Electric Company of Mexico, and his tacoustic gun." the seat of the trouble was discovered.

The ffacoustic gun" consists of a tube whose frequency is in accordance to that of a microphone fixed to one end, in such a way that it produces a thin beam of sound which causes a greater or lesser reflection when the microphone is pointed toward the places from which the sound strikes. This reflection in turn is captured by a two-sided microphone, situated in the place where the echo was heard. Through the use of this gun it was observed that the echo diminished when the apparatus was turned toward the curtains covering the entrances to the theatres, but increased when the apparatus was turned towards the wall . despite the fact that they were covered, as previously stated, with a 90 per cent soundabsorbing material.

Through the use of curtains and padding, the echo was eliminated, but these hangings completely undid the effect of the interior decoration. It was then that the solution was discovered. The acoustic material was placed in angles of 90 degrees, at the back of the theatre hall. thus obtaining the complete disappearance of the echo, since the sound wave had to strike twice against the acoustic material, losing 90 per cent of its force tw0 times before returning to the place where the echo had been objectionable. In other words, instead of returning 10 per cent of the sound force after one contact with the absorbent ma 1945e-THEATRE CATAlOG

[was \ was.

THE CINE TERESA in Mexico, D.F., some of the problems involved in the renovation of which are discussed in this article, has become one of the Mexican capital's 10p motion-picture theatres. That owners Arturo Ceballos and Julio Castro selected the right man in Francisco J. Serrano as the architect is apparent from these pictures. The proscenium of the Cine Teresa, as viewed through the bronze stop on top of the balcony Front, reveals a simplicity accentuated by the classic figures of the Three Graces and the Nine Muses, so befitting the house.

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1945 Theatre Catalog, 4th Edition, Page 191