Here's a new 'Sound Science' question for y'all: Take 4 tone generators tuned to 200, 400, 800, and 1600hz. Turn each one on individually, and set it's volume to 80dB. Now turn on all4 at the same time. What will be the measured dB? When I change the volume of any of the 10 bands on my AVR, the total perceived volume changes. So I'm guessing it's some integral of the individual frequencies?