First Subwoofer box I ever built. $0 budget just using scraps around the shop. Boss told me not to build a box it's cheaper to buy a prefab, and I took that
How to Build a Subwoofer Box | KICKER®
How to Build a Subwoofer Box | KICKER®
Subwoofer Enclosure Box Kicker Q Class 2-12 35HZ Build Plan - Etsy New Zealand