15 L7 box

I wrote a post about a week ago and a few people told me that I should get a small sealed box for my L7.  So I took the advice and this sh*t hits like crap.  I have A Jbl BP. 1200.1 and this mess doesnt drop or hit worth a sh*@.  I took time and read the kicker manual and it says that a ported box wins in all categories over a sealed one.  Especially is SPL.  It says a large to medium ported box would be best for a 15 inch L7.  What do you guys think about this.  Do you think a larger sealed one would work best.  And what do you guys think about v tech boxes.  I have seen alot of people using them in contest over sealed boxes what do you guys think.   And I want SPL and alot of it I will dealed with SQ later thanks. 

I say go with the large ported box and let it rip!!! I think that would give you want you are wanting. What is a v tech box anyways??? Never heard of that name before.

make a big ported box, kickers  need lots of airspace

Even if the sub is in a small box it should hit. It sounds to me like there may be another problem. 1st off how do you have the Xover on the amp set? It should be at 80 Hz. Also how do you have it wired? And were dose the input signal from the amp come from (head unit, hi to low converter, EQ)? And was it a replacement or a new setup??

the best bet on a square kicker sub is a large ported box from my experience with them. we usually put in about 2 to 3 sets a week and only go sealed if we cant build a large box. the last on i did was 6 cf. for 2 12s in a ext cab chevy 1500 and it was hitting like a 140 last i heard.everyone calls me subwoofer

bbmecp would you happen to live in cali? i need someone to make me a custom box for my 15 inch L7