Since you already have a sub and amp driving, then you would not need a 5-chnl like the Kicker zxm700.5. But, you do not need a 6-chnl either, to run 6 full-range speakers. Just about every full-range 4 chnl amp out there will easily run 6 speakers. There are also a few 5 chnl amps on the market that will work fine as well.