7 ply birch plywood... junk or??

[helotaxi 5,000+ posts]

0.6 cf per chamber tuned to 40 hz. I think I had 15 in of port per side. It was built for a pair of Assassin 8s (first series) and I was powering the crap out of them so I didn't want a chance of port noise. Couldn't tune any lower without worrying about the response getting muddy as the group delay went through the roof. They sounded great within their range but fell on their face on the lows.

 

[emilimo701 10+ year member]

Bump this up

About to build an enclosure for a 15" at about 5 cubic feet. I am thinking of using 5-ply birch. I went to home depot and was very turned off by a couple sheets of MDF being frayed at the end as if it were made of (albeit dense) layers of paper meche. Are there any plywood haters or cautionary tales that I should hear? Or is it the general consensus that the only physical differences do not affect the speaker? Right now I'm going with the assumption that 5-ply birch is just as fine if not better than MDF.... plus i would love a stained wood finish.

Oh and I have X- and Y-axis dowel braces in my current design, but that's it.

 

[RAM_Designs 5,000+ posts]

Plywood is more rigid than MDF, but harder to work with as far as cutting goes. I've used the 5-ply stuff before with no issues, but not on large high powered setups. I'd assume it'd hold up fine because it is in fact more rigid than MDF, and if you brace it properly, should hold up very well. The only thing that sucks with using the 5-ply and 7-ply stuff is predrilling because the bit always has a tendency to just go into one of the plys instead of staying exactly where you want it to go. But if you have a roundover bit or a sander of some sort it'll be easy to make everything flush.

 

[gunz4me2 10+ year member]

Free wood is the best kind unless it's particle board.

I've been known to use particle board (i.e. Low Density Fiberboard) for test enclosures. In fact, I just made a super cheap test enclosure out of it for my wife's vehicle!

I've also used Home Depot Birch and had no issues with it other than the fact that I discovered a void the hard way, while tightening the T-Nuts. Just take my word, that is NOT when you want to discover a void. I also learned that hurricane nuts are better than t-nuts for situations like that.

 

[RAM_Designs 5,000+ posts]

Yeah, be sure to get void-free if possible.

 

[1rockford1 5,000+ posts]

i used .5 mdf the othere day for the fist time not bad i went with smaller screws . hmmm

 

[DonH 5,000+ posts]

MDF is a little more forgiving as far as cutting and rounding over and such. Birch ply likes to "chip". But in my experience it works just as well as MDF. But as mentioned, make sure to brace any large areas. (the same with any material)

yeah if you have your router speed set to low OR are trying to cut more than 1 layer at a time.

OP if its free why complain? it will work nicely. there are two reasons why birch is a great material, ONE is its LIGHT AS HELL COMPARED TO MDF! and two its DENSE AS HELL!

 

[RAM_Designs 5,000+ posts]

there are two reasons why birch is a great material, ONE is its LIGHT AS HELL COMPARED TO MDF! and two its DENSE AS HELL!

I think you mean rigid or strong, as it being dense would contradict your previous statement of it being light compared to MDF. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[schackel 10+ year member]

i used birch on my build. it was harder to work with but its soooo much lighter. it was only 30 a sheet here. its just as strong if not stronger than mdf

 

[helotaxi 5,000+ posts]

I'm at a loss as to why people think that good ply is harder to work with. Pine ply, sure, the resin in the wood will burn up a saw blade in a heartbeat, but birch ply is great. It makes actual sawdust, too instead of that talcum powder crap that gets all over the garage and can never be completely cleaned up. As long as you use sharp router bits and saw blades I find it much easier to work with than MDF.

 

[gunz4me2 10+ year member]

I'd rather work with Birch than MDF.

 

[RAM_Designs 5,000+ posts]

MDF powder ftmfl.

 

[audio-pro714 10+ year member]

Plywood has voids randomly with in the layers and it isn't dense enough for a trully acceptable enclosure. But then again that's truly a sound quality reason.

 

[Louisiana_CRX 5,000+ posts]

the best wood for a sub box is Marine grade 3/4 Baltic Birch....its good to use cheaper shat for a rough in if your not sure what you want but once you decide its something your gonna keep spend the extra monies to get the marine grade Baltic Birch...its dense, lite weight and just about impossible to warp...

 

[iLL Ridge 10+ year member]

Dense does not equal light weight. Rigid maybe.