Here's my final plans for a subwoofer...ridicule them... (1 Viewer)

[Brett Creider]

The amp has already been ordered, as well as the driver...

Parts Express 250watt Remote Control amp
Adire Audio 15" Tempest

I've looked around at local hardware stores and based on the materials they sell I've planned on the old fashioned MDF box...

It shall be 24"x24"x24" give or take. The MDF is sold in 24" x 48" peices for $7 each...3/4" thick...so here is what I plan...

(All attachments using ProBond + Wood Screws)
1) Buy 4 MDF 2x4's...
2) Cut each MDF in half to create 8 2x2's...
3) Cut 1 side each of 2 2x2's by 1.5" (3/4" x 2)
4) Take 2 2x2's to make base, cut a 15" hole in one and a 16 in another (I am not sure on the actual measurements but I'll get exact ones when the driver arrives. I am just going to do a flush mount using double thick MDF like I've seen done before, so don't take the hole measurements too literally)
5) Take 1 2x2, cut it in half to a 2x1. Make 8 3" x 1.5" peices. Use 2 peices each to make 4 90 degree angled legs. Attach legs to base. (Maybe use some MDF left over from holes to brace legs?)
6) Take the other 1x2 and make 4 24"x3" braces, 2 going either way.
7) Mount driver in base. Cut out hole for remote and amp.
8) Start attaching the front and back. Then the 2 sides will fit in between those. All 4 peices attached to top of base.
9) Fill with some insulation/filling stuff I saw at Wal Mart after I wire it all up. Attach top.
10) Have fun.


Sound good? Should only cost $45 to build the box and I'll laminate it or paint it later....

 

[GrahamT]

It does sound good. Like you I just ordered a Tempest and cant wait for it to arrive. My box is 18"x18"x40" and 3/4" thick MDF. I am going to use about 200wrms. I cant wait for deep accurate tight bass. Have you used winisd or lspcad?

 

[Brett Creider]

I've messed with WinISD with my headphones and these can't-crank-it-up-and-let-them-do-the-bass Sony's with 8"ers in them...

Headphones start to drop off after 40 I think (Sennheisers)and quit at 20 and the Sony's start to drop off after 50 and quit at 30.

I have been without any kind of bass in here for a month so in a few days when this thing is built I can not WAIT to crank it up. I have gotten some good CDs together and everything ready to go when the sub is ready...it's gonna be sweet..

 

[GrahamT]

If you download lspcad from adire you can input your room, sub and other specs and it will give you a lot a data. Like an spl graph, impedence curve etc. According the the program, my tempest will hit around 101 to 102 dB at 20Hz. I cant wait to try it out.

 

[Brett Creider]

I'll DL it if I can find it...

 

[Brian Bunge]

If the MDF is exactly 2' x 4' you can't cut one in half and have 2 2x2 pieces. The width of the saw blade will remove around 1/8" of material and will throw off all of your dimensions. I'd just set the fence to cut 23.75" and cut the largest pieces to that size. Adjust all other measurements accordingly to get everything to fit properly.

 

[Brett Creider]

Ah I never thought of that...thx

 

[PaulDF]

The MDF 4 * 8's I've bought have all had an extra inch both ways. Not sure how universal this is though. I thought everything was BIGGER in Texas!

 

[Eric Eash]

so just make your calculations 1/8" smaller, or use a bandsaw and lose way less on each side.

 

[Brett Creider]

what calculations? all of them or just those 1.5" cuts?

 

[Eric Eash]

i was referring to your problem of cutting a 2'x4' in half to make a perfect 2'x2'. brian had said you would throw off your dimensions, or calculations, so i said you could just use a bandsaw.

 

[Brett DiMichele]

Wouldn't it be great if they made a Kerf'less saw? (Hmm I
guess it wouldn't really be a saw then..)

I say Use the Fricken "LASER"

 

[Brian Bunge]

Paul,

That's true. MDF is 49"W x 97"L. But if you buy it pre-cut into 2x4 sheets, it may be exactly 2x4, or it may be slightly larger. I'm guessing they would probably be cut exact. But I haven't used any in quite some time so I can't be sure.

 

[Frank Carter]

All the 2x4 MDF sheets I've bought at Home Depot have been slightly larger. I think each measurement was larger by around 1/2".

 

[Brett Creider]

All I want is a solid fit I don't care if it's exactly 2' tall or something I just don't want any gaps I gotta fill...

 

[Frank Carter]

If you download PE Box(free), you can input the thickness of the wood and your target internal volume and it will just spit out what dimensions you need to cut each panel to.

http://www.partsexpress.com/resources/pebox.html

 

[Bob Kavanaugh]

so just make your calculations 1/8" smaller, or use a bandsaw and lose way less on each side.

Not to notpick, but you assume this man has a 24" bandsaw? Most i've seen are 12" and benchtops are 9".

Also, screws make boxes ugly, you can try to fill them, but they'll nipple or crater on you, depending on what you use. I suggest using a poly glue like Gorilla glue, holds mdf together like nothing you've ever seen. Make sure to dampen the wood first (read the instructions), and use lots of clamps.

Finally, a priceless tip (at least I think). Leave a sliver of overhang on each joint (so that the side with "endgrain" is marginally longer than it should be. Use 60 grit sandpaper on a palm sander and sand that edge down. Presto! It looks like you have made perfect cuts and the glue joint will disappear.

If you really want to get fancy, smear in and sand off Durhams water putty on all cut edges. This will prevent the mdf from sucking up the paint (or whatever finish you use.) Water putty is also an ideal wood filler if you still decide to use screws, because it won't shrink.

Look at my link for an example of what not to do. My DIY sub boxes are screwed and painted without treating the cut edges. You can clearly see screw nipples and panel edges. I have since learned the magic of gorilla glue and water putty.

Best of luck!

 

[Brett Creider]

I was thinking of getting a big role of laminate to go over it anyways so I don't know if screws would be a problem. I wouldn't trust my paintjobs to torn out anyways...

 

[Eric Eash]

bob- what i was talking about is cutting the 2'x4' in half with a bandsaw since the blade on a bandsaw is thinner than a tablesaw or scrollsaw or circularsaw.

If the MDF is exactly 2' x 4' you can't cut one in half and have 2 2x2 pieces. The width of the saw blade will remove around 1/8" of material and will throw off all of your dimensions. I'd just set the fence to cut 23.75" and cut the largest pieces to that size. Adjust all other measurements accordingly to get everything to fit properly.

the shop i use has a bandsaw that will cut through 36" of solid wood. it's a really nice and expensive shop though.

eric

 

[Brett Creider]

Well the amp got here friday and holy CRAP is it huge. It looked so small on the site but it's like 12" x 12" and 20 lbs...damn it's heavy...I like it lol it weighs as much as the entire sub in the HT...

The remote looks kinda cheap but that's ok...

I ordered the tempest this morning so it should be here by thursday, which is when I build the box me thinks.