I know.. Its basically limited to SI BM's, Another pair of SSD's, RL-p's, D6's, Tc-1000's, Treo SSI's, and I thank thats about it unless anyone else can come up with anything. Right now the Tc-1000's are lookin pretty good
I just put in 2 TC 10000 10's I was limited to 5.75 inches of mounting depth They sound excelent and get really low considering I have them in a .65 cuft box. I just tested them with Late Night Tip and **** it was turning heads as I drove down wilsire in L.A. I have my box downfire and I'm a bit short on depth between the floor and woofer but they still sound great. With 6.5 inches of mounting depth you could do a downfire and lift them higher than I can in my Titan. It would be an excelent setup.
Honestly I found myself turning the volume knob DOWN, but I'm not as insaine as some people on here.
I'd go for the TC1000's or Si BMs (I have not heard the BMs) or maybe AA Arsenals (have not heard them either) if they hit as low as TC (or close to it) and maintain the SQ from the Assassin.
In my small enclosure I think the SQ from the Assassin was a little, but noticably more accurate than the TC's, at least on higher frequencies, it also had a little more clearance in the downfire due to having less excursion but the difference in output and their ability to get low make up for the difference if you want SQL. I personaly like downfire subs under the rear seat of the truck, however I guess tests prove you can get more output from upfire when you flip the seats up (I leave my stuff hidden so It does not get jacked) and I think subs sound better and shake the truck more with downfire.
Is that a Chevy? My friend has 2 JLW6V2 10's and I can't say anything bad about them either. I'm not a JL fan anymore but W6's are great for SQL and you might be able to find some for cheap. Just an alternative, I'm not sure if his W6's sound better or worse but **** these TC's hit low, I can't imagine them in a larger sealed box., or ported. Ic an't stand the sound from my other box in my titan tuned around 40-50 htz, it sounds REALLY good on some songs but gets boomy on others. At first I thoguth it sounded great considering it was ported, untill I installed my AA Assassin and it's been getting more fun from there.
You might consider getting 10" TC 1000's Downfire them with 3-4 inches of clearance rather than pushing the limits with 12's (if you are near them)
BTW!!!!!!!! I'm not sure 12" D6's will fit, the 10" Verson is 6.2 inches their specs online are INCORRECT I could not fit the 10" in my truck. I would imagine the 12" would be deeper and not fit into your 6.5 inches of munting depth. Better check them out in person before you buy. I'm not overly upset anymore but I paid $50 to have D6's shipped and never even saw the box (company called post office to have it returned). Basicaly just money into the toilet so I would hate for that to happen to you) However the 10" D6 would fit, but you would have to make a new baffel / box which is sounds like you might need to do anyways to have an SQL setup 40htz is SPL all the way.