Okay, so I just got a 2012 Soul (base) with 16K miles for a steal this past weekend and I realized...I need subwoofers. However, the reason I got the vehicle is because I like all of the room in such a small vehicle. So, I was looking at subwoofers that would fit under the seat. I did quite a bit of research online and settled on the Sound Ordnance B-8PTD from Crutchfield audio. Instead of just going with the one, I got two (one for underneath each front seat). Anyone else have this type of setup? Looking forward to bumpin' up and down the road.
The amount of room under the front seats is actually rather staggering. You could easily fit 8s in a small box, or even 10s and still have room. A 2 channel amp placed in the footwell on the passenger side, with wires tucked under the carpets would make for a very clean install. You could also make some custom boxes from 3/4" MDF and a handful of wood screws and wood clue. Just make sure you try and get the cubic footage as close as you can to the reccommended footage for the subs.
I installed a powered 8 (Clarion, I believe) under the passenger seat of my brother's Soul. I tied it into the factory system. It adds some good bottom end, and was a worthwhile upgrade.