Is this box design strong enough ?

[Bigun]

I would like your advice on my design for a sub (attached) - specifically does it look strong enough?

I want to minimize construction complexity or loading it down with acres of plywood so I am relying on some internal bracing to keep it all nice. With drivers operated as a pair there should be some cancellation of acceleration forces for the box overall but there will be plenty of forces within the box structure.

I have gone with a pair of crossed braces which touch (glued to) all sides of the box near (but not at) their centre-lines. I have positioned the amplifier in a corner to allow a brace to contact along the length of the side it is cut into for better strength.

But the push-pull design introduces some complexity on one side.

 

[Ron E]

IMO, it is best to not have any unbraced distance more than 15cm on any panel, especially if using thinner material. You might even want to look at 10cm between some sort of bracing on every panel.

 

[Bigun]

That should be possible if I cut some extra pieces and put them between the main braces and the walls. There will be quite a few off-cuts of ply left over from cutting the main panels so I could install a liberal amount of them (keeping an eye on the reduced volume).