Downfiring sub box...... (1 Viewer)

[MarvinJr]

Now that I have a box built to suffice my bass head, I can now take my time and build a nice box. I was searching and found a thread somewhere of a guys build that I really liked. Not sure where the thread was, but just wanted to give credit to this guys idea. I think he said he stained it with red oak stain, anyway I am sure someone knows of this guys build.....very nice work he did.

I did some figuring and can get 3 and a half cf easy.....haven't decided on which 12" to go with yet, so I haven't got an exact height yet.....so I can match the cf up. My plan is to build this box out of .75 mdf, and then skin it out with .5 veenered ply. And use 1 by 2's or whatever I decide on for the corner trim, and also using them as the 4 feet to raise it up off the ground. Gonna do this box right, using the better bracing, and foam as needed. Seeing as how I am in no hurry I can take my time and see how much difference it makes.

Anyway I will post pics as I go if anybody is interested. And tips and criticizim welcome......bring it!

 

[MarvinJr]

Just a rough drawing, realized the brace is across the opening for the amp......so obviously the amp placement is gonna change. lol

 

[MarvinJr]

www.hometheatershack.com/forums/diy-subwoofers/16974-first-subwoofer-build-css-sdx15-pics.html


Not sure how they feel here about links to other forums, but here is the box I was talking about. Sorry if that was a bad idea to link that.

 

[Robert_J]

The brace is fine. Just notch it out a little so the amp will fit.

1/4" veneered plywood works just fine and will be cheaper than 1/2". Tightbond II glue will work best in glueing it to the box.

I've linked to the Dan Marx site on one of your other threads. The www.creativesound.ca/ site has a few designs for the SD12. Take a look. If you don't use one, they give an excellent example of proper enclosure building.

A guy who built a sub with red oak stain. That's an easy one. Was it Robert Charles' LMS project a few threads below this one?

 

[MarvinJr]

I found the thread....posted above.

Thanks for the link.

As for the brace....I can easily just mount the amp in the top half, and not worry about notching the brace.

 

[MarvinJr]

I have been looking at all the different options for cutting nice holes. What do yall use? I am want to get some sort of setup for cutting holes, but not sure which way to go. I saw one of the rotozips come with a circle cutting guide, just never messed with the rotozips.....always figured them for being on the toyish side....not quite on the level of routers. Just looking for some opinions on what everybody uses.

 

[MarvinJr]

I have some form of OCD, because I went to HD and bought a little MDF, and slapped this together since I posted earlier.

 

[MarvinJr]

Was wondering about other supports.....Any suggestions? Is it personal preference, or will they affect the sound?

 

[Robert_J]

OCD? Really! At this rate your post count will be higher than mine by December.

If you properly attach the 2nd layer of boards you won't need any additional bracing. This will take patience. Glue it and let it dry for 24 hours before handling it.

I use a Skil plunge router with a Jasper circle cutting jig. Yes, you can use others or build your own but this one already has calibration hole drilled in them. If you need an 11 7/16" hole then you drill a pilot hole, put the pin in the proper hole in the jig and start cutting.

-Robert

 

[MarvinJr]

Gonna get a router and order that Jasper jig, I have seen that jig on PE and liked it compared to other stuff I have seen.

As for lining the inside of the box......I have seen the egg crate looking foam used, would carpet padding do the same or similar? I have a roll of new carpet pad and it would be nice if that would work. Didn't figure it would, just asking.

 

[Robert_J]

You need open cell foam. I think that carpet pad is closed cell to make it springier (is that a word?). A properly designed sub doesn't need it. I use polyester batting (aka pillow stuffing) from Wal-Mart to make small, sealed enclosures seem larger.

-Robert

 

[MarvinJr]

Ahhh, I do know the difference between open cell and closed. Didn't figure it was the same, but hell I got a roll of that padding I still have yet to find a use for lol.

 

[MarvinJr]

 

[Robert_J]

Why are you painting the inside of the box? You need to at least sand the edges down to bare wood before gluing that last side on. Wood glue doesn't bond well with paint.

-Robert

 

[MarvinJr]

Just to seal and preserve the mdf, was planning on making the back removable.....but decided against it.

 

[MarvinJr]

Gonna dressup the baffle with some kind of trim inside the bottom of the box, and stain it up!

 

[MarvinJr]

Anybody wanna see a pic?

I got 2 coats of stain and just put the 1st coat of poly. Made more work than it should have been cause a few of the joints weren't exactly flush, and I didn't sand them down.....I had stained it twice and put a coat of poly on, then had to go back and sand everything flush. Not a big deal like it was, but why not fix it.

 

[MarvinJr]

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