Box materials, construction tecniques

[JonP]

Hi all...

So, as I near the time I need to really get going on a set of wedding present speakers, I'm pondering construction materials.

I'm probably going to build a set of Modula MT's, or Nat P's.

After recently re-reading Jon's article on the original M8a design, and it's MDF/Oak layer methods.... I wanted to ask about similar layers and get suggestions. Someday, I want to buy an accelerometer, and actually do studies on this.. but that ain't likely before I cough up these!

I have available to me (thru the local Rockler) some good quality 5/8" Baltic Birch (11ply) for low cost. They stock these odd 23"x23" offcut pieces, for $4 each, great for smaller boxes and some even have a nice figure. I know it's kind of thin, but I was thinking of doing attached panels of MDF or other stuff a la the M8a IV... and probably two 5/8" layers of BB for the front baffle....

So, what think you Jon? 1/2" or 3/4? MDF? Go for 1/4 or 1/2" Oak or other hardwood? Use some flexable adhesive, or two part epoxy? Dampening layer suggestions? I'm also concerned with extra $$, as well as weight. This won't be the highest end system... so best bang for buck is where I'm wanting to go...

All suggestions are welcome... perhaps this could become an informative thread for all kinds and $$ levels of box construction......

[ThomasW]

The MDF with oak bracing was the technique designed to reinforce the Woodstyle box that was used in the M8a article. The WS box is veneered particleboard.

For a scratch built box use 5/8" BB doubled or 5/8" BB with a layer of MDF. Make in internal brace from the 5/8" BB that looks like the one in the PE boxes

[JonP]

For a scratch built box use 5/8" BB doubled or 5/8" BB with a layer of MDF. Make in internal brace from the 5/8" BB that looks like the one in the PE boxes

Kind of what I was thinking... I'm looking at how my BB pieces will saw up with the needed panel sizes... I end up with a lot of long strips of 3" and 5-6" wide leftovers. Looks like it will resemble Jon's treatment of the Woodside box after all..

I was also trying to get a feel for what benefit dissimilar materials might have, i.e. BB and MDF, or BB and thin HDF, vs. just thicker BB.

The BB is pretty stiff stuff... just a tich ringy at this thickness...