LOC or Amp with Sp Level Inputs?

[sierra248]

I'm trying to decide if I should get an amp with speaker level inputs or run a LOC behind the unit itself. Is there any disadvantage/advantages either way. I want the cleanest sound possible using A non-Bose Speed3 Stock Head-Unit. Also How do I hook up my sub woofer with David Navone FOUR CHANNEL OEM TO AFTERMARKET STEREO ADAPTER NE-774V . This is 4 channel and with a sub, that's at least 5 channels? Can I have a Stock Head-unit and the fader with a Sub?

Thanks in advance for any info!

 

[sierra248]

I guess a 5 channel amp would work but i wanted to go with the new alpine powered box. http://www.crutchfield.com/S-ZfqoxBn7KzA/cgi-bin/ProdView.asp?g=51000&I=500PLV7

and use a 4 channel amp