It won't. Gain setting isn't rocket science. If your right now a bit low on the hu side of the gain, your just making up for it at the amp's gain knob level. You can turn up your HU, but then your amp may need to down to compensate, just because you HU signal wont' be clipped doesn't mean you won't still clip at the amp by turning the HU up higher, if you left the amp alone. I'd keep it as is if you like it, if anything turn it up higher at the amp level if you want to raise your gains. power is power regardless of where your gain knobs are, assuming your not clipping at any stage. Right now if your listening to non bass heavy music but want to add some extra bass to it, you can by simply turning the subwoofer up on the HU. Are you hearing any floor noise from your subwoofer, of course not, so turning up lowest level of signal does you no good. That' the only inherent advantage.Dude are you sure about this? so you're saying my sub output should be turned to full to get 4V? I can try that tomorrow but I doubt it'll change anything.