Question about building speaker cabs

[big kurka]

I know from reading everywhere that it is recommended to use 18mm or 3/4" birch plywood. My question is would it be a big deal to use say like 5/8" birch plywood. I've been wanting to build a pair of 2x12 cabs kinda oversized like the marshall mf400 cab. I'm not going to be gigging with these cab they are going to be for my garage where I do all my playing. Is the 18mm reccomended for a tonal thing or is it more for durabilty? Any help/knowledge would greatly appreciated.

 

[Bfeeney]

Re: Question about building speaker cabs

I made two 1-12" cabs out of 3/4" ply and it sounds good to me. At the very least, 3/4" would be easier to screw into than 5/8".

 

[uOpt]

Re: Question about building speaker cabs

You can trade thickness for a bit more work. You put reinforcements inside to support the centers of the sides.

 

[SlyFoxx]

Re: Question about building speaker cabs

The thicker and stiffer the box the less it will color the sound. This is always a good thing when building Hi-Fi speakers but less important for guitar cabs. Part of the great tone of old fender amps is from finger joint pine that resonates more than 3/4 marine grade birch. So the answer is there is no correct answer...just differences in sound.

 

[big kurka]

Re: Question about building speaker cabs

Thanks for the replys everyone. I guess I'll stick with 3/4"

 

[Gr8Scott]

Re: Question about building speaker cabs

I built a cab out of 5/8 birch ply (it was supposed to be Birch) from Lowes Hardware. The wood was kinda soft, so I wonder about it's content. I bought a Kreg jig and very carefully built this cabinet over a series of evenings and then threw a couple of leftover Peavey XXX Sheffield speakers in it once it was fully assembled. I built mine with a variable port that can completely shut off the port if you want and the cab goes more or less imperfectly sealed. I have the port slightly open and it adds a nice bit of bottom (but not too much) to the overall sound.

I reinforced this cab like no other. It is as solid and as heavy as a boat anchor.

I don't have any finished pics because I haven't completed it yet. I got the thing built and haven't bothered to coat it in truck bed liner just yet. I'll get around to it one of these days. It was a fun project and I don't regret it one bit.