I ran my 4 channel amp the following way. front channels to front speakers, and rears to my sub. this is running off the stock stereo with line convertors, so I left all the rear speakers connected to the stock monsoon and the result is nmot bad, I have to turn the fader more to the back because the new amp is much much louder, and so I turned the fader just enough to provide a rear fill to give extra sound, so its not to loud, and the sub is turned up pretty loud this way I can turn down the bass on the headunit, which means the stokc subs will not push to much and ruin the nice soud-since they sound muddy, this way they produce just a little bit of sound.