for a temporary thing incase u need to fade the back speaks...u can hook up the free pair on one side channel and the alpines on the other side...then u may be able to fade using the balance button...
i.e. if the free pair is hooked up on the right side of the amp...u lower the balance on the h/u to lower the volume of the rear set...
but this hook up is just if u really want to fade...and would not be useful if u hook up a 2 ch. sub amp...then the left side or right would be louber than the other...but if u use a mono sum amp then maybe you can pull it off
i.e. if the free pair is hooked up on the right side of the amp...u lower the balance on the h/u to lower the volume of the rear set...
but this hook up is just if u really want to fade...and would not be useful if u hook up a 2 ch. sub amp...then the left side or right would be louber than the other...but if u use a mono sum amp then maybe you can pull it off