8 channel sound art installation

[jamezilla]

I'm trying to design an 8 channel audio setup for a sound art installation, but I'm having a bit of trouble juggling all the variables. I have some unusual requirements. The basic setup will be eight speakers arranged in a circle with a 10ft radius. I'll be building the speakers to spec as well.

I'm considering just using a bunch of LM386s, but that's mostly because I'm completely ignorant.

Here's my requirements:[list=1][*]12V DC power supply[*]Low power consumption - it's running off a car battery (possibly with solar trickle charge)[*]Decent enough sound quality to reproduce synthesized human speech - it sounds crappy already, so it doesn't need to be audiophile[*]60dB at 8ft - I know this depends on the speakers but I'll probably be using a pair of cheap 0.25W 8 ohm speakers in each cabinet (any recommendations appreciated here too).[*]Robust - it needs to be able to run unattended for days out in the desert heat[/list=1]
You can read up on the project details if you're interested in what this thing will be doing.

Thanks!

[jamezilla]

Should I just buy a couple of these Amp32 kits and call it a day?
http://www.41hz.com/main.aspx?pageID=105

I think they're way overkill for what I need, but they appear to be very high efficiency and look well-suited to running off a car battery.

[pinkmouse]

They would would certainly work well in your application, though you might need quite a few solar cells to power the rig. As for speakers, in your position, I'd be looking at cheap 4 Ohm car jobbies.