2 layers is NOT adequate. Possibly on the top piece since it is so small, but you'll want 3 on bottom and sides and 4 on the back and 6 on the baffle. Once you are ready to build the baffle ONLY cut the first sheet and dry-fit it in place, post pics, take measurements and post here so we can give you some input on how it looks before you cut and glue another 5 layers. Once the top, bottom, sides, and back are on you'll have a much better idea of how much volume/area you have to work with and how to finish the baffle.
It is looking much better though.
Looks 1000x times better....but is that particleboard?
Shocker Mike has done a fair bit of SPL testing with particle board. Assuming adequate bracing/thickness WITH RESIN it will perform identical to MDF with resin, without resin is is going to be over 1dB down.
Why do you say that los?.....and yes its particle board, i got about 40 sheets for free, and i was very dissatisfied with my wall so i figured fuuck it, I'll start over and see how well the particle board will hold up. If it does...hell yeah, if it doesnt, oh well, it was free. Who cares what kind of wood it is, as long as it works who fuccking cares?....it'll be painted anyways. And most likely a few layers of some type of resin and some paint.
You will definitely want to plan on coating it with resin (and it will soak it in pretty well by all accounts). Consider doing the top bottom sides and back BEFORE you put up the baffle. Call US Composites for some cheap resin and use a 6" hot dog roller to apply. Have Acetone handy and work in small batches.
I figured with the right bracing and enough glue between the layers would help strengthen it.
You need more layers!
Rigid and airtight. 2 layers is going to flex terribly. 3 on the sides top and bottom should be sufficient, use no fewer than 4 on the back and 6 for the baffle (when it comes time). If the wood is free your only cost is a few bucks worth of glue and screws. Internal bracing may cause unwanted turbulence and will certainly make it more difficult for you to climb in the box and wire speakers, seal, paint, etc. I'd much prefer going thick on all walls than skimping out and trying to put a band-aid on it later by turning it into a spider-web of bracing. If you find you still have to brace later, so be it, but you should shoot for having enough strength without. Also, no need for those 2X4s in the corners if you're fitting those pieces snug and planning to resin. It looks rather haphazard. One of the things I most dislike about mine is that I had to use them around the back, but I'm compromising there in order to have the back open up so I can use it for cargo space when needed.
Ignore papermaker. He can't even type a coherent sentence and has yet to post any actual real world builds or results of any consequence.
