Help with a sub box build

Hutchinson KS

Description

I need to build a more complex box for my truck. I’ve built a few before but they have been wedge or rectangle with a slot port. My issue is the port. I’m basically building a rectangle with a wedge added on for a single 12. I’m unsure how to calculate the port size and length so I can tune it to 32hz. So if anyone can help I’d really appreciate it.