I just want to get some reactions here-

I was talking to someone at an audio shop today about my car, and he wondered why I was looking for a 6-ch. amp if I was already going to install another amp for my aftermarket sub.

He was suggesting that I use a 4-ch. for my front and rear 6.5's and another amp for my 12, and that I just leave the rear deck 6x9's sitting there doing nothing. His logic was that if i'm going to install a 12, the 6x9's won't be necessary.

Does that sound normal to you?

 

I wouldn't just leave the 6x9's in there. They are doing something - blocking audio transfer from the sub into the cabin, also, with a significant sub, they'll be acting as (albeit slightly) passive emitters, out of phase due to the pressure waves from the real sub.

I'd say get a 2 channel and only use front components, and a separate single channel for the sub, but if you're insistent on using all four channels, using a 4 channel and a single channel is a much more flexible way to do it, and gives you many more options to choose from.

 

So then by that logic, whether I use a second amp or not, 6x9's shouldn't be part of the picture after I install my 12?

I think what I'll do is run a single channel sub and a 4 channel mid amp. I'll start with replacing the front components like you suggest, and if it doesn't sound right to me I'll just replace the rear components. I'll have to figure out this 6x9 solution in the process.