I "think" your problem was the 2V pre outs on the Alpine. My setup sounds amazing for just a head unit swap. (Not that the OEM was all that bad) Yes, there are better/more expensive options, but I am more than pleased with the sound. I tried the speaker levels first and didn't care for the sound. The volume was there, but just didn't sound crisp/clear. Seemed to be a bit of distortion with much volume. Just my $0.02. If your Kenwood has 4V pre outs, I think you'll be fine.