I dont really need low, loud is the objective (approx 40hz & up) & the listening point is outside of the vehicle (anywher between 20 - 50 feet away).
Space shouldnt really be an issue since most likely its a big vehicle I will be using it in (looking to change rides in a few years). I am considering a pair of horns BUT the fact that it will not be used like the traditional car audio subwoofer is the reason why I am looking at this.
I am considering getting something custom built from david at psi to meet my needs (should be 4, 2 or 1 ohm to be used with car audio amplifiers).
Its sort of different how we do it here in this country, competitors line up, basically go at it & the loudest wins. The winner is chosen by ear not by the meter (like in bass boxing).
I have been observing many of them have started removing the backseat & building enclosures to fill the void to house subs. There goes the use of the cabin because basically all you have is the front half of the car's cabin remaining & the 4 doors are wide open throughout the competition.
I have been meaning to get into it one of these days hence the reason why I am looking at getting a sub for this specific application. Correct me if I am wrong but car audio subs wont work here & HT subs are too high of an impedance to match car amplifiers.
The use of a horn may very well be plausible because I will have a lot of space to play with in the van or if I so happen to buy a car to be used solely for this purpose the by all means, i'm going all out!
Those were some of the smaller ones, we have some like these as well: