Full scale model investigation on the acoustical protection of a balcony-like façade device (L).
The acoustical insertion losses produced by a balcony-like structure in front of a window are examined experimentally. The results suggest that the balcony ceiling is the most appropriate location for the installation of artificial sound absorption for the purpose of improving the broadband insertion loss, while the side walls are found to be the second best. Results also indicate that the acoustic modes of the balcony opening and the balcony cavity resonance in a direction normal to the window could have a great impact on the one-third octave band insertion losses. The maximum broadband road traffic noise insertion loss achieved is about 7 dB.
Freeway noise and high‐rise balconies
The sound levels on balconies above the 8th floor of high‐rise buildings situated 200 ft or so from freeway edge‐of‐pavements were found to be about 10 dB higher than those occurring on the ground floor. Equivalent sound levels on these balconies during the day were in the range 70–80 dBA depending on the size of the freeway; these sound levels are as high as those at ground level 50 ft from the edge‐of‐pavements of the freeways concerned. However, the use of sound absorptive material on a normal front‐walled balcony was shown to produce substantial noise reductions: treatment of the ceiling alone resulted in a 4–5 dB reduction, while a 7–8 dB reduction occurred with the addition of absorption equal, in Sabins, to a little over one‐third the area of the balcony surfaces.
A simple one-third octave band spectrum shaper
Abstract Simple modifications to a readily-available band-pass filter set produced a device with which each one-third octave band of a noise spectrum from 2 Hz to 10 kHz could be controlled. The resulting spectrum shaper was a simple and cheap tool for use in testing human reaction to a variety of noises.