The amp has both left and right high to low inputs. Do I just need to wire to one channel or wire them both up to the sub signal?
Without specific information about what it is you're installing, generally you'd be connecting both channels to the high level inputs. So a R + and -; and a L + and -. This means that the amp receives the full range from the HU, and it will output the appropriate frequency to your sub. But, if you're taking the factory speaker lines for the sub, and connecting them to the HL inputs of the amp, then you only have one channel anyway........and this is where my headache began.....>>>>
Déjà vu!
I bought my mates 3.0R a few weeks ago, and this is my story:
Sub was shaking the crap out of the parcel shelf, so I decided to go for a 10" Polk in a box running off the factory amp. ......Wrong. Way too underpowered. Bought a 4 channel amp to run the sub off for now, then maybe upgrade the door speakers later. Integrating that with the factory HU= more trouble than it's worth, so I bought a new HU. (Clarion VX404AU- my first Clarion)......... Well, what do you know- it doesn't fit in the factory fascia! *buys new fascia.
Long story short- next weekend, the whole Mac system is coming out