I just hooked up my factory sub even though I didn't need it. Anyways I think it doesn't sound too hot so I wired it to a switch that I glued to my centre console. Now I can turn it off and on whenever I want to make the seat shake when my dates aren't going well and I need a hand! :E (Jk) Seriously I'd recommend using a switch since it doesn't play pure bass, it plays everything including vocals. Sounds bad.