I'm not gonna aim you your answer, but I'll give you some info here. Your question is a bit vague. It all depends on what you're trying to do, and the gear you have. Are you using this 4 channel amp just for the sub(s)? How many Subs are you talking about? I'm gonna assume that you have one driver, and you are using the 4 channel amp for it. Now we have to get into power handling and resistance. Also is your amp 1/2/4 ohm stable when bridged? Is your sub a dual 2/4/8 ohm driver? If you can help narrow down your particular gear, I'd be happy to lay out a doable plan of action for you.