1" birch

[mat3833 10+ year member]

Anyone used this stuff? It's like 20 layer full 1" thickness Baltic birch. I'm FINALLY about to get my box cut and I can't decide if I want to eat the airspace and double baffle the top(48wX30d), or if I just want to brace it with 1" dowel. The entire enclosure will be made of the 1" birch, and the top is the only panel with a size over 18x18.

Subs are 18" TC sounds pro 5100s, about 50 pounds each, power is from a Smart 5 at 2 ohm.

Trying to get the panel layout done and get a final quote so I can finally finish my build. I'll toss up a picture of the panel layout shortly.

Matt

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[mat3833 10+ year member]

Outside dimensions are 50x33x24

Still working on final height to make sure I can put the subs in, it may end up being 22 tall.

 

[huberoy123 10+ year member]

Outside dimensions are 50x33x24

View attachment 47455


View attachment 47456

Still working on final height to make sure I can put the subs in, it may end up being 22 tall.

What vehicle are you putting it in. Seems that you will need lots of space. Will 2 18" subs be too much for your space. Just curious.

 

[mat3833 10+ year member]

What vehicle are you putting it in. Seems that you will need lots of space. Will 2 18" subs be too much for your space. Just curious.

It's roughly 15 cubic feet, I'll do that math once it's actually built. It's going in a 2003 jetta. You can check my build log for more info. And people have put alot more cone area than 2-18"s in a jetta before, I'm sure ittl be fine. I've already got a single 18 in there now.

Matt

 

[huberoy123 10+ year member]

It's roughly 15 cubic feet, I'll do that math once it's actually built. It's going in a 2003 jetta. You can check my build log for more info. And people have put alot more cone area than 2-18"s in a jetta before, I'm sure ittl be fine. I've already got a single 18 in there now.

Matt

Thanks for the reply. Good luck with your project.

 

[audiobaun 5,000+ posts]

Whip out the wallet for the price on the Birch

 

[JasoninDLH]

Dang…You gotta post some pics up during your build. Definitely gotta see it when it’s done!

 

[mat3833 10+ year member]

Whip out the wallet for the price on the Birch

Yea, it's not cheap, total cost plus shipping is going to be about 1200ish, still working out details. But rather than 4 sheets of 3/4 it will either be 1 sheet of 1" and 1 sheet of 3/4 or 2 sheets of 1". The bottom, back, and large side panels are all going to be against the body of the car, so 3/4 would be fine, going with 1" because why not. Just need to decide if I REALLY need 2" thick top or if I can just 1" the whole thing on 5k with a few dowel braces.

Matt

 

[mat3833 10+ year member]

Dang…You gotta post some pics up during your build. Definitely gotta see it when it’s done!

I have a build log. Just search "violently expensive", lol.

Once I have the box I'll be able to finish the amp rack and wiring and whatnot.

Matt

 

[audiobaun 5,000+ posts]

Yea, it's not cheap, total cost plus shipping is going to be about 1200ish, still working out details. But rather than 4 sheets of 3/4 it will either be 1 sheet of 1" and 1 sheet of 3/4 or 2 sheets of 1". The bottom, back, and large side panels are all going to be against the body of the car, so 3/4 would be fine, going with 1" because why not. Just need to decide if I REALLY need 2" thick top or if I can just 1" the whole thing on 5k with a few dowel braces.

Matt

You should be able to get by just fine with 1" and dowel bracing just fine on 5k. I did fine on 2 layers of 3/4" MDF alone on approx 8k for 4 12s

 

[mat3833 10+ year member]

You should be able to get by just fine with 1" and dowel bracing just fine on 5k. I did fine on 2 layers of 3/4" MDF alone on approx 8k for 4 12s

Thank God, REALLY didn't want to fork out an extra 280 for another sheet of 1"...

Matt

 

[hispls 5,000+ posts]

I would not consider buying meme lumber for a car audio project and I do not believe 1" thick alone is really going to make it on a 15 cube box. Just buy 3/4 MDF or ply or whatever you can get the best deal on at your local lumber source, double baffle, and add bracing on all large panels. People very much under-estimate how much flex you get out of panels. My baffle is 34X36" or thereabouts with some extra 2x4s glued in between the woofers and at 5 layers MDF it still moves noticeably without steel bracing to the center.

 

[mat3833 10+ year member]

I would not consider buying meme lumber for a car audio project and I do not believe 1" thick alone is really going to make it on a 15 cube box. Just buy 3/4 MDF or ply or whatever you can get the best deal on at your local lumber source, double baffle, and add bracing on all large panels. People very much under-estimate how much flex you get out of panels. My baffle is 34X36" or thereabouts with some extra 2x4s glued in between the woofers and at 5 layers MDF it still moves noticeably without steel bracing to the center.

LOL, meme lumber. While I definitely appreciate that comment for what it is, this is not meme lumber in the slightest. One of the builders i work with at the granite shop just switched to it this year for certain cabinets. It's expensive, but it's zero void, 19-22 layer, full birch plys. I was going to double baffle 4 of the panels to 1.5" with the cheap 7 ply 3/4" and make the top 2.25", but Dan showed me a sample piece of the 1" vs the 3/4" 15 layer they use.

At 24" the 1" was deflecting 1/8th with 500 pounds in the center. The 3/4 started making cracking noises at 400lb after deflecting about 3/8ths. This stuff is freaking strong, and the plys are 45 degree layout, not 90 so you get alot more uniform strength.

I don't know all the math and whatnot and I don't know wood that well. But if the main custom cabinet guy switched to it over 1.5" glued panels(cheaper for him) for outdoor kitchens with granite countertops, I'm inclined to listen when he suggests it.


I think I'm going a full 2" thick on the top panel. The front/sides will still just be 1". I don't see myself running anywhere near full output on these for very long, and I won't be getting more power either. So 5k on a 14 cubic foot net sealed enclosure for 2 18's.

Matt

 

[hispls 5,000+ posts]

At 24" the 1" was deflecting 1/8th with 500 pounds in the center. The 3/4 started making cracking noises at 400lb after deflecting about 3/8ths.

OK, now do OSB or 3/4" MDF/cheap ply with a single 1" brace in the center.

It's your money, and ultimately you need to weigh your priorities here, but as far as I'm concerned you're not making furniture or something that you'll need to look/access inside so apart from nicer veneer if you plan to stain/poly I don't see a lot of incentive to quadruple my cost of lumber on a car subwoofer enclosure.

 

[mat3833 10+ year member]

OK, now do OSB or 3/4" MDF/cheap ply with a single 1" brace in the center.

It's your money, and ultimately you need to weigh your priorities here, but as far as I'm concerned you're not making furniture or something that you'll need to look/access inside so apart from nicer veneer if you plan to stain/poly I don't see a lot of incentive to quadruple my cost of lumber on a car subwoofer enclosure.

Ahh, I gotcha. I'm going with birch for some weight savings and I'm going to put some poly on it to make it look nice and waterproof it. I also do want to be able to take the top off so I can access the port Cutout from the front down the line if/when I decide to run it ported.

Let's not talk about OSB, that **** is awful. As far as MDF, I could go 1" MDF as well, but I'll be adding an extra 80ish pounds to the car over the Birch. And a regular plywood isn't bad either, but I'm still paying 120/sheet for decent void-free 9-layer 3/4. And I end up using an extra sheet, so the cost is pretty much the same.

I'm looking at adding a simple cross brace inside the enclosure, but I haven't fully committed to it because of the odd shape. There will be at least 2-1" dowels inside the enclosure on the top, splitting it into 3rds a bit behind the sub cutouts. There may be a front to back dowel as well, but if I decide to follow through with the port, I have no real space for a dowel in the center. Keep in mind that the bottom, back, and sides will all be bolted to the body or basically locked into place once the doors are closed. The bottom is on the rear seat pan, the back is the trunk/rear crossmember/strut tower area, and the sides match up to the doors once closed(expanding foam will fill the gaps in the future, not the cheap "gap fill" stuff either. I have 2-part hard cure foam available from work.

Matt