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Discussion Starter · #1 ·
Just because someone will ask....it's a 10W7 on a JL Slash 1000/1.

Let's assume you have your perfect sealed volume figured out and all your specs are spot on. You're going for a SQ enclosure....not booming...just tight and accurate although the sub is probably overkill.

What's your thoughts on the perfect enclosure build ? One that's solid, doesn't "ring" when you knock on it, etc.
Thoughts on whether an angle on one end is really necessary ?

I'm getting ready to build what will hopefully be my final enclosure for this system remodel so I want it solid as it can possible be.

My thoughts are, start with a 1 1/2" thick front baffle with the pieces glued together. The sides will be slightly angled to incorporate my console lid but the front and back ends will be perpendicular because that's what I need to accomplish the final look I need. Should I throw in an internal angled baffle on the rear wall ? The enclosure will be right at 22" long but only 12.5" tall....given the short sidewalls are any internal braces needed due to the length and the sub choice ?
What about the ringing I'm getting from my current test box ? It's lined inside with rubberized bedliner. Is figerglass resin a better choice inside to deaden the wood ?

Just looking for opinions on the best tricks for a super solid enclosure. I have zero concerns over weight added or anything like that....I just want it as dead as possible.
 

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Just because someone will ask....it's a 10W7 on a JL Slash 1000/1.

Let's assume you have your perfect sealed volume figured out and all your specs are spot on. You're going for a SQ enclosure....not booming...just tight and accurate although the sub is probably overkill.

What's your thoughts on the perfect enclosure build ? One that's solid, doesn't "ring" when you knock on it, etc.
Thoughts on whether an angle on one end is really necessary ?

I'm getting ready to build what will hopefully be my final enclosure for this system remodel so I want it solid as it can possible be.

My thoughts are, start with a 1 1/2" thick front baffle with the pieces glued together. The sides will be slightly angled to incorporate my console lid but the front and back ends will be perpendicular because that's what I need to accomplish the final look I need. Should I throw in an internal angled baffle on the rear wall ? The enclosure will be right at 22" long but only 12.5" tall....given the short sidewalls are any internal braces needed due to the length and the sub choice ?
What about the ringing I'm getting from my current test box ? It's lined inside with rubberized bedliner. Is figerglass resin a better choice inside to deaden the wood ?

Just looking for opinions on the best tricks for a super solid enclosure. I have zero concerns over weight added or anything like that....I just want it as dead as possible.
What kind of ringing are you talking about? What is your current box made out of? None of the boxes I've built exhibit any ringing. They all sound like solid wood.

A double thick baffle is a great start. Otherwise, 3/4" MDF as its likely the most dead material you'll be able to use. Glue everything together and tighten with clamps. Do not use screws if you can help it. If you must, understand that screws are only there to replace clamps, not to hold the box together. I would recommend Titebond II wood glue.

Use binding posts instead of a terminal cup. Instead of fiberglass resin, consider using a 60/40 mixture of wood glue and water brushed on to seal the walls from moisture. Its equally effective if you're going to carpet the box afterward.

If you can fit any, use some dowel rods for bracing. Cut them 1/16" shorter than the length you need so that when you screw them in from each side, there's pressure on the enclosure walls to further prevent them from flexing.

I'm using a double thick baffle (the second one is for a recess) for my IDMax10 with 3/4" MDF and the same wood glue method and NO bracing, and there is absolutely ringing.
 

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Discussion Starter · #3 ·
It's hard to convey a sound through typing....but my test box is 3/4" mdf with a 1 1/2" front baffle and as mentioned, lined inside with spray on bedliner then covered in carpet just to make it blend in for now. When I rap on the top with my knuckles it just doesn't sound "solid", it's a sort of odd hollow sound that I can't really relate to anything you may be familiar with....it just doesn't sound "solid" if that makes any sense.

With the fiberglass resin I meant lining the inside of the enclosure with it, one to add some strength and weight and 2 to make double sure it's all sealed up.

I also plan to use your modeling service when I get back home to see if your numbers coincide with mine, more to double check my numbers than anything else. You ask for some dimensions I can't provide without being in the truck though.
 

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It's hard to convey a sound through typing....but my test box is 3/4" mdf with a 1 1/2" front baffle and as mentioned, lined inside with spray on bedliner then covered in carpet just to make it blend in for now. When I rap on the top with my knuckles it just doesn't sound "solid", it's a sort of odd hollow sound that I can't really relate to anything you may be familiar with....it just doesn't sound "solid" if that makes any sense.

With the fiberglass resin I meant lining the inside of the enclosure with it, one to add some strength and weight and 2 to make double sure it's all sealed up.

I also plan to use your modeling service when I get back home to see if your numbers coincide with mine, more to double check my numbers than anything else. You ask for some dimensions I can't provide without being in the truck though.
Well, hollow and ringing are entirely different words, lol. A hollow sound is normal. That's just the frequency of you knocking on the wood traveling around the box and being transmitted through the sub cone. Its absolutely no indication of how well the box is put together. It doesn't sound solid because, well, it isn't. Its a box.

If you use wood glue as I noted, you will have zero leaks at the seams. MDF alone will not leak. I know someone will be a smartass and tell me that if you put 100PSI over an inch of MDF, it will leak .001 cubic inches of air over 100 years, but for all intent's purposes, it doesn't leak.

Fiberglass resin is strong, but it will not add any consequential rigidity to your box. It cannot replace a good brace installed inside the box. IMO its damn near useless to line the inside of a sub box with. Anyone who heard a difference using it had a poorly built box from the start. I'm really not sure where the practice came from but its quite unnecessary. If you don't believe that it won't do a thing in adding ridigity, lay some over a sheet of paper in equal thickness to what you'd lay inside the box, let it dry, and try to bend it till you break it. Then, try the same with a 3/4" piece of MDF, with your bare hands. You'll understand then why I say that its inconsequential.

It may make the joints stronger, but again, if you build the box correctly with wood glue and clamps, it won't be an issue.

See this thread:

http://www.diymobileaudio.com/forum...ough-gasket-sealed-enclosure.html#post1430650

Avoid terminal cups and use a gasket on the sub mounting surface and you'll be fine.
 

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I think I understand what "ringing" your talking about. Every enclosure I've ever built sounds like a small tight drum when I knock on it. Is that what your talking about?

I may be wrong, but any well built enclosure is gonna resonate at some frequency. So maybe that's what your hearing when you knock it?
 

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What you need is bracing, and plenty of it. For the best results, use at least 3/4" of plugged & sanded birch plywood for all the panels, and line it with either fiberglass or acousta-stuff. Resin is great for sealing the seams from the inside, but don't go nuts with it - by itself it doesn't contribute any strength; all you need is enough to coat the inside thoroughly once.
 

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Well, hollow and ringing are entirely different words, lol. A hollow sound is normal. That's just the frequency of you knocking on the wood traveling around the box and being transmitted through the sub cone. Its absolutely no indication of how well the box is put together. It doesn't sound solid because, well, it isn't. Its a box.

If you use wood glue as I noted, you will have zero leaks at the seams. MDF alone will not leak. I know someone will be a smartass and tell me that if you put 100PSI over an inch of MDF, it will leak .001 cubic inches of air over 100 years, but for all intent's purposes, it doesn't leak.

Fiberglass resin is strong, but it will not add any consequential rigidity to your box. It cannot replace a good brace installed inside the box. IMO its damn near useless to line the inside of a sub box with. Anyone who heard a difference using it had a poorly built box from the start. I'm really not sure where the practice came from but its quite unnecessary. If you don't believe that it won't do a thing in adding ridigity, lay some over a sheet of paper in equal thickness to what you'd lay inside the box, let it dry, and try to bend it till you break it. Then, try the same with a 3/4" piece of MDF, with your bare hands. You'll understand then why I say that its inconsequential.

It may make the joints stronger, but again, if you build the box correctly with wood glue and clamps, it won't be an issue.

See this thread:

http://www.diymobileaudio.com/forum...ough-gasket-sealed-enclosure.html#post1430650

Avoid terminal cups and use a gasket on the sub mounting surface and you'll be fine.
Fiberglass resin by itself is actually brittle. Its strength comes from when it is used in conjunction with the matt. I assume that most people apply resin inside of their boxes to create an air tight seal. I havent used this method myself, but I figure that the MDF would soak up alot of the resin. I dont see why this wouldnt create a good seal though. I personally just put a line of wood glue on the inside seams. If the box is built well, it shouldnt have any leaks to begin with.

What you need is bracing, and plenty of it. For the best results, use at least 3/4" of plugged & sanded birch plywood for all the panels, and line it with either fiberglass or acousta-stuff. Resin is great for sealing the seams from the inside, but don't go nuts with it - by itself it doesn't contribute any strength; all you need is enough to coat the inside thoroughly once.
I agree. The stronger the box the better. Hell, Ive seen enclosures made of concrete, and granite. Can never be too strong. I believe that the JL Audio high output (HO) enclosures are made with 1" thick walls. I thik if you use 1 1/2" baffle, 3/4" walls, and a couple well executed braces you will be fine.
 
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