US dept of Labor extract a.k.a. OSHA dBA Slow Hours/day (max) 90 8 92 6 95 4 100 2 102 1 1/2 105 1 110 1/2 115 1/4 Yamaha C3 in 8.5'x7' room (small, no?) Temp/octaves 88 - 90 dBA Unisons 96 -105 dBA Unisons 110 - 115 dBA (fast) Young Chang G-175 in same size room Temp/oct 89 - 93 dBA Unisons 98 - 106 dBA Steinway B - student playing Ravel = 98 dBA Yamaha C3 - student playing Beethoven = 96dBA 2 cu.in chain saw - 14" bar = 105 dBA idling//117dBA wide open/no load Friendly trumpet professor 121 dBA @ 4' (nice friend...) Readings on pianos were taken from approximately ear position, at first... The S&S D's and SD-10's were equally loud to the ear distance, but as they are in large halls the attenuation was what you always were taught. The sound level decreased exponentially inversely with the distance. The practice rooms were a different matter. I found that I got the same readings at the tuning pins, at ear placement, on bench beside me, on bench - meter turned away, and on floor as far away as I could place it. In fact, at one place on the floor I got _higher_ readings. -must have found an antinode. -- Conrad Hoffsommer Ignorance doesn't kill you, but it will Luther College make you sweat a lot.-Haitian proverb hoffsoco@martin.luther.edu
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