2 Kicker 8" Solo-Baric L7's :Questions
 

You guys are going to get sick of me pretty fast. I'm like that little girl from Animaniacs that keeps asking "Why. Why. Why. Why. Why."

I'll tell you what I'm thinking, then you tell me what your thoughts are on my thoughts.

Here goes...

Firstly, the amp I'm using puts out 1120W @ 1ohm, 680W @ 2ohm, and 410W @ 4ohm.

I can purchase two 8" subwoofers. Either a pair of DVC 2ohm that I could run in series to have a 1ohm load on the amp - essentially providing 560W to each speaker. Or, I could buy two DVC 4ohm, run them in series to have a 2ohm load and provide 340W to each speaker. 8's are a little harder to come by, and their configurations are less varied as well. However, I have found the KICKER 08S8L72's and 08S8L74's that would allow me to run either one of the setups I mentioned.

The 1ohm setup would actually provide power that exceeds the RMS of the subs, while the 2ohm setup would provide slightly less. The Max is 900W.
Which setup, on paper, would be a 'better'?

The next topic is enclosure sizes. The Kicker website recommends .33cu.ft (Minimum) and .75cu.ft (Maximum) sealed enclosures. Would there be any benefit of using a smaller box for one, and a larger for the other? My logic leads me to believe that between the two I'd have a broader range of bass, as opposed to an isolated peak frequency with two identical boxes. Would there by a detrimental effect to my sound if I had two separate, dissimilar sized enclosures?

You guys are the best.

Why not just go with one 15" dual 2 ohm L7? You can get away with running a bit too much power into that setup. Thats an extra 100 watts per side. I wouldn't run two different enclosures because you change the response of the subwoofers. This might seem good to have different frequency peaks and response curves, but the result usually is cancellation (like wiring one speaker out of phase with the other). You are better off focusing on making a good box for both subs.

Why not one 15"? Limited room, as I like to keep my subs in my back seat.
Right now I'm planning on building a trianglular box, about 10" wide, and putting that right on the middle of the backseat. The subs will face the roof at a 45 degree angle. That way I can still have passengers on either side. Right now, my giant band-pass box sits behind the drivers seat, so all extra occupants have to enter on the passenger side, which can be inconvenient.
I'm under the impression that eights are able to provide better SQ as opposed to higher SPL. I want to be able to have nice sounding bass, with the ability to pound on occasion. Wouldn't this be easier to achieve with the 8's?
Alright, so two different cu.ft boxes may be a bad decision. Would I really know if it was not going to work without attempting it? Are there any tests done to find out, that I could read up on, online?
What I need to do is go listen to a couple eights. Problem is, NO ONE has them hooked up!

Choose the sub that fits your application best. An 8" sub won't necessarilly sound better than a larger one just because it is smaller. It depends on the quality of the sub and the quality of the install.