Jim,
dB is a logarithmic scale. 1/100 is -20dB so 97dB - 20dB = 77dB. Purdue says a passenger car at 65 mph at 25 ft (77 dB).
David
Jim,
dB is a logarithmic scale. 1/100 is -20dB so 97dB - 20dB = 77dB. Purdue says a passenger car at 65 mph at 25 ft (77 dB).
David