Thanks to several member posts, we have finally assembled our noise monitor amplified by an LM386 that activates red, yellow, and green LED's. A 9v battery powers the opamp. The board and LED's use Arduino/USB. We need forty of these, all battery powered. Can this be done with just one battery?
Well probably not because from what I understand they will need about an amp or more, so even if it worked you would run out of juice very quickly.
Try using a power supply that can handle this kind of loads, but then it wouldn't be so mobile 