Hey guys, I recently upgraded my headunit to a pioneer deh--580mp, and the pre outs are at 4v compared to the 2.2v i used to have on my old one, some aiwa model. My sub is hitting a lot harder, and is playing louder!! I checked the gains, and everything appears to be set right, does a higher output just give better quality, or do i really have too much power going to my sub?