I used my tempest in the car with great results. It seemed to hold up well.. although I DID have to send it back because it became out of alignment. Whether that can be attributed to the car environment, I don't know, but others as well as myself have had great results with Shivas/Tempests in the car. I believe someone actually hit 151 db or something like that at a competition with a single Tempest. Anyway, to answer your question.. if you go to any car audio forum, and search tempest/shiva/brahma, you'll find that there are many people using Adire drivers in their car. Andrew
My windows are open a lot and I park outside every day. This results in temperature changes, and I've even left my windows open when it rained and my upholstry got soaked.
After a while, the foam surround started to fade slightly, but no performance hits. To fix this, I applied a generous coating of armorall to coat the entire driver and ports, and it now looks better than new, plus is holding up quite well to the elements.
I believe the armorall protects it well because my tempest is exposed to direct sunlight unlike many of them out there.
Mark, you've made a wise choice for a car subwoofer. I don't have a shiva in my car, but I do have a PE 12" DVC which is very similar. I only have 200W RMS going to it and it shakes the crap out of everything. Wish I had a little more power though.
With the cabin gain you get in the car compared to the average ht room, the sound will blow you away. Depending on what type box and size of the box will be the factor of wether or not it will sound boomy or musical, just like it would in a ht room.