When calibrating the EP500 sub, how much gain (in dB) should I expect when moving from minimum gain to maximum gain on the volume control/knob of the amp?

I currently have my sub calibrated to 75 dB (to match the left front speaker) and the volume control/knob is at approximately 7:00 with the receiver's trim at -10 dB (left front speaker is at -3 dB). How much of an increase (in dB) should I experience if I increase the sub's amplifer gain control to its maximum setting while keeping the receiver's volume/settings consistent?

Thanks in advance!