It's not always that simple it takes measurements, and modeling to even glimpse at the end result. Not only that your goals and mine would be different.
It sounds like you want loud I personally would suggest a ported box built on the larger side of things tuned to the mid 30s. It really depends on your cabin gain to see where your box needs to excel and where it can roll off.
Or a 6th order designed by someone who has experience with them. I don't have experience with them enough to give much input beyond my current knowledge. I don't even want to try and think about an 8th order. Bandpass boxes are big depending on the situation you may be better off dropping from 1 12 to 2 10s or even 4 8s in a slightly larger box and then you will have more voice coil to absorb the heat so more power can be applied.
I wish buck was feeling well since he was a good resource for box design, shredder was doing them too at one time.
My truck has had several systems from 1 eclipse aluminum 12, 2 JL 13tw5, 2 dd 506s, 2 sa10v2, 2 Dayton ho 10s, 2 DD 1508s and my next box is for what essentially is 1 10 in a 6th order granted it uses 2 nvx 10s but the output will be similar to only 1.
My goal post is forever moving. Hell I even had a system in another truck that was 2 kicker comp 10s on like 800w in what had to be the perfect sealed box for those subs combined with that truck. It wasn't loud but that was one of the cleanest setups I had. Wasn't happy with the output and those 10s got sold and replaced with something else. This hobby is basically a dog chasing it's tail in the pursuit of perfection
