it you have a larger wire it will not affect the sound quality - but what i see 99% of the time the install of larger power wire and no upgrades to the grounding. Remember, electricty travels in a circle to your battery -0 you might have a nice big fat power wire, and a nice ground at the amp to metal frame, but did you upgrade from frame to battery ground? shops normally do not do this and it can be the cause of many problems.