box specs

[b-dubs89]

i have heard a few people on smd say that manufacture box specs are not optimal .would like some input as to the box jl is recommending . i plan to run 3 of these subs .

jl audio 13w1v2-4 .

what ever box i build it will be over built to some degree , with bracing and double thick in some places

Wall Thickness 0.75 in / 19 mm Front Baffle Thickness 0.75 in / 19 mm Volume (net int.) 2.625 cu ft / 74.3 L External Width (W) 23.75 in / 603 mm External Height (H) 17 in / 432 mm External Depth (D) 18 in / 457 mm Internal Slot Port Width (SW) 1.5 in / 38 mm Internal Slot Port Height (SH) 15.5 in / 394 mm Internal Slot Port Depth (SD) 31.5 in / 800 mm Port Extension Length (EL) 13.5 in / 343 mm Tune to 26.0 Hz F3 26.0 Hz