Do you know how easy this information is obtained.When you bought it it should have came with an owners manual.In the owners manual is the manufacturers recommended box sizes for sealed,ported and slot vented boxes.
JL recommends a sealed enclosure that has an internal net volume of 1.25 feet ^3
They recommend a ported box with an internal net volume of 1.5 feet ^3
Simply visit the JLAudio website and click mobile audio and then subwoofers and select 12W6v2 and then click download the owners manual.You must have Adobe.