I've played sine wave files from a CD through an oscilloscope connected to the outputs of my head unit and outboard equalizer before, it was a very cool way to see how far you could go before the signal distorted.

Could the same be done for the empeg? Rip a sine wave?

(PS, I didn't leave the gains maxed, in fact I normally set all of mine all the way down and only up what is necessary to get a pre-EQ balanced sound. Also - I notice at 0db on the empeg, that it's a perfect match when switching sources on my CD player / head unit. That is, going from tuner to CD to empeg, etc. all have the same relative volume. so for me, odb is perfect.)