Need a good sub box

[HVDE30]

Hello all, I am looking for a good single 12 or 10inch sub box design for my 1990325i sedan. I have the fold down opening back seat and want to place the sub therer.

[jbontke]

I have seen what you are asking for on this guys instagram: https://www.instagram.com/e30dreamin/

[moatilliatta]

I made a MDF adapter for an Alpine Sub / AMP combo to fit that space. Works well and light weight.

Something similar people are putting under seats.