Box building material.

[audiofanaticz]

So who will paypal me $30 so I can take a 4by8 sheet out of my garage prop it up and put my 340lbs on it?

I will refund the payment if it does not break.

[audiofanaticz]

I mean you keep preaching this advantech osb, but even in your wall you use the cheap osb.

Sure the wood is manufactured by Hubar which is also who makes advantech, but advantech is just another line of products they offer.

[audiofanaticz]

and yes, it was TaylorFade that found a bunch of rocks in his plywood when he cut it.

Took me for ever to find the picture he posted here.

I have no reason to doubt this picture to be faked since he seems very very honest on his amp and battery test videos.

Id say he is more than credible.

You can even see the burn marks on the wood where the blade has jammed up.

Also this is typical for any type plywood, especially plywood that uses douglas fir for the inner cores.

Sure finding rocks in it is odd and then some, but the voids and knot holes in the layers are abundant.

[hispls]

I say it goes back to the manufacturer of the subwoofer you plan on using. They make prototypes and hand them over to bassheads to torture test them for a given time frame. Find out what they used to make the enclosure they tested the subwoofer with. Or what works best for their product.

People who say this works and that works......it's because it worked for them. Taking their advise as gospel only to use "their theory" on a different brand?

Hard to make a generalized statement on which wood is best based on that.

Stiffness, rigidity, flex. Remember all wood flexes. lol. Bracing "x" few inches helps minimize it. What's the golden rule for panel runs before adding a brace?

I was about to bring up this topic since Devin's 4th order will be powered by @ 1800W.

BAA brought up a good point about doubling up on the wall thickness. Ram's design has the top and bottom panels as one panel thick. All other panels are double walled.

I should have enough room to double the top and bottom panels to minimize panel "flex".

See, now you have me saying it!!!

-Frank

I don't think there's any rule as far as what to do. Of course any wood or manufactured wood product will flex, length of the panel, power, and material type and thickness are probably the critical factors there.

From what I can tell, the best builds are over-built to the point where the builder reaches the limit of his budged, space, or weight constraints. It's easy to say "double wall all around and triple on the baffle." But what if you're trying to squeeze 5 cube net into CRX? That's when we start to compromise, adding bracing, guessing which walls are narrow enough that they likely won't flex substantially, or possibly stepping up to a stronger material (if we can figure out what that is).

[hispls]

And before you say its rigid and doesn't flex

Care to try that test with a sheet of MDF or plywood? I'd wager just about any 3/4" manufactured lumber would flex or break with a full grown man bouncing up and down on a sheet like that.

Speaking of which. Check out this "bendy" MDF. Flared ports or interesting shaped boxes? http://www.bendymdf.co.uk/introduction.htm

Link don't work...

Also.. I don't see the point in testing the bend strength/resistance in a full sheet.. under no circumstances should a box use a full sheet with no bracing..

if you want test out these panels.I say test with smaller pieces, maybe 12"x12"... then build identical enclosures out of your panels your testing.. and measure difference in output between your test boxes.. weight them too!!..

I'm assuming the test panels will be, advantech, mdf, real 11 ply birch, and maybe others..

EDIT: I'm assuming this is like the mdf u linked..

http://www.amazon.com/Neatform-Bendy-MDF-Sheet/dp/B001DT4TVS

I just clicked a link to :Bendy MDF. So it appears to be just pre-cut to bend. The site didn't show the innards just some finished products that looked pretty cool.

I'd really like to see some legitimate testing or data of a variety of 3/4" material. I think too small of a test box and there wouldn't be much difference at all. I suspect the preferable materials would pull away once you got to the point where you'd want to start bracing or doubling up.

And before you say its rigid and doesn't flex

Care to try that test with a sheet of MDF or plywood? I'd wager just about any 3/4" manufactured lumber would flex or break with a full grown man bouncing up and down on a sheet like that.

Speaking of which. Check out this "bendy" MDF. Flared ports or interesting shaped boxes? http://www.bendymdf.co.uk/introduction.htm

If you say so.

What you use is not the end all be all its just what you choose to use.

Just throwing this out there, all the extremely loud builds on here or most places for that matter are built from mdf or plywood, you aren't about to change the game with fucking osb.

If my goal was to get loud i would take my advice from the pros, just sayin.

The problem is the real pros aren't posting build logs online. Check the dB-Drag leaderboard and tell me how many of the guys on the first page are posting tips on what methods and materials they use. Everybody is dancing around the issue either to not hurt feelings or to justify whatever it is they use, but nobody can show me any testing or hard evidence to quantify which materials are better for what and by how much.

I asked the team who has the loudest builds in the region and I was told Advantech is good. That's what the lumber yard said they were delivering.... if I got something else, oh well. I got fucked... live and learn and I'm planning to build up to the B pillar at some point anyway.

Everything else aside, would you not care to know how much better 150$ a sheet pedigree birch plywood is over the 30$ a sheet at Home Depot? How those compare to MDF? I'd really like to quantify what precisely it is we're trying to do and the pros and cons of our options. Some actual data may even lead us to formulate some guidelines of when to double up layers and when and how much bracing is appropriate.

So who will paypal me $30 so I can take a 4by8 sheet out of my garage prop it up and put my 340lbs on it?

I will refund the payment if it does not break.

LOL.

[Broke_Audio_Addict]

Sigh............

[audiofanaticz]

The materials being used doesnt mean its the best or the worst.

I do know I never see anyone using osb, the last time I seen particle board being used was 2001ish.

Terry brocks has the loudest trunk car and yet to be beat and doing very high numbers out of a honda accord trunk with the rear seats installed (but folded down).

He is using mdf, and screws I swear every inch or less... I was always taught and told that screws this close together weakens the bonding joint along with creating a lot of hairline splits even if you predrill.
But like I said he is the loudest trunk car doing something like 158s db drag legal and 162s usaci outlaw. I think the next closes people to him in his classes are around 5dbs away...

Does this mean I will stop using brad nails and start screwing boxes with a screw every inch of the way? hell no.

Also its worth mentioning that these boxes are single layer mdf, with minimal bracing, the 2nd pick is 2 18s iirc in the trunk...

[Broke_Audio_Addict]

You know that enclosure flexes like a mofo though.

[dsw422]

OP, if you want to see tests done, either you will have to do it or pay someone on here to do it.. there is a reason noone has tested advantech. It's not the material of choice since it appears to be in the same family as osb...

[hispls]

You know that enclosure flexes like a mofo though.

Gotta wonder if it's vibrating in sympathy with his system resonance and actually gaining?

OP, if you want to see tests done, either you will have to do it or pay someone on here to do it.. there is a reason noone has tested advantech. It's not the material of choice since it appears to be in the same family as osb...

If anybody has the time, means, and access to materials I'll kick in 30$ worth of cash or trade towards materials to get such a test going.

The materials being used doesnt mean its the best or the worst.

I do know I never see anyone using osb, the last time I seen particle board being used was 2001ish.

Terry brocks has the loudest trunk car and yet to be beat and doing very high numbers out of a honda accord trunk with the rear seats installed (but folded down).

He is using mdf, and screws I swear every inch or less... I was always taught and told that screws this close together weakens the bonding joint along with creating a lot of hairline splits even if you predrill.

But like I said he is the loudest trunk car doing something like 158s db drag legal and 162s usaci outlaw. I think the next closes people to him in his classes are around 5dbs away...

Does this mean I will stop using brad nails and start screwing boxes with a screw every inch of the way? hell no.

Well his results certainly speak for themselves. Fascinating that 1 layer no bracing does what it does for him. Most of those panels are rather narrow though, but still. It even begs the question of whether there's something more going on there than the stiffness of the wood even.