I'm running an S15L7 in a 5 cuft. vented enclosure. The bigger the box the better the sound for the L7. A 6 cube box would do well. At 6 cuft. make the port 3.5x16.25 and 13.75in. long. Then give the sub 1000watts. Make sure you amp has a subsonic filter too.
I've heard of guys going with 6cuft. sealed enclosures for more sq. The vented will definitely be loud, but sq will suffer some. IMO go vented the sub will pound.
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