Study of Room Noise (11/17/2005)

79.5 dB [all AC machines running]
73.5 dB [only #1]
74.5 dB [only #2]
76.0 dB [only #3]
74.5 dB [only #4]
68.5 dB [all AC machines off, only UPS]

The following figures are power spectra of the noise in the room, with different combinations of the four different air conditioning units running. The legend in the top right hand corner of each graph explains which AC units, if any, were running when the power spectrum was taken.

Graph of total room noise (all AC/UPS operating).