Buying wood... thoughts on my box?

[k_schutte 0]

So, i am HOPING this is the final box design for my SPL-15 as I am going ot buy some MDF here in a couple hours. HOWEVER i just thought since this is my very first box design done by myself I would throw it up here for you'all to check out and let me know what you think. Nothing Fancy, just a simple ported box....

Edited June 19, 2009 by k_schutte

[vladd 26]

i didn't run the numbers but a quick glance says it "looks" ok. I'd suggest at least some form of bracing considering how large the box is.

[k_schutte 0]

fixed....

Edited June 19, 2009 by k_schutte

[vladd 26]

definitely a slot port. I'll run all the numbers in a minute if someone doesn't beat me to it

[rushnrun 14]

needs the back, top and bottom plates braced (even a simple 2"x2" brace will help. with that large of a panel you'll have flex.

my general rule of thumb is if it's over 18" (long or wide) it needs a brace.

I didn't run the numbers but looks good.

[k_schutte 0]

I was planning on using some 1-1/4" dowel... one left/right and one up/down, would that work good enough?

I have my old box and stuff laying around and considered "window bracing" but I am trying to keep the box volume as high as possible!

[vladd 26]

window bracing would be better than dowels. And with a box that large, i'd gladly sacrifice a little volume for proper bracing, it'll help more than the volume it displaces.

2x4 would work fine, dowels can work but i usually have 2x4s laying around so that's what gets used (way too lazy to cut out window bracing)

[k_schutte 0]

Leaving right now... I will probably see what they have up there and then decide what ot do for bracing. I was thinking threaded rod might be a good choice too... I guess we will see what i come up with. Wish me luck!

[rushnrun 14]

"window" bracing is easier/cheaper than threaded rod... the dowels will help... better than nothing (as long as you can get them secured w/out cracking the wood) also more expensive than the 2x4 route.

[k_schutte 0]

Ended up getting some 2"X2"x8' for like $1.48~ so i went that route. Don't have a nail gun anymore so i just got some "self pre-drilling" screws and liquid nails. It's over 90* outside so i just had Home Depot cut it all for me (except the circle) and I am going ot throw it together in my "office" where it is nice and air conditioned! I am literaly sweating from just walking to my house form my car 3 times (its about 10ft)

ANYWAYS... forgot to get paint for teh port so i guess I am just going to skip that part, probably won't carpet teh box anyways for a little while so it isn't really a big deal. I am just ready for some damn bass back in my car!!

[wenn_du_weinst 1]

what about double baffle?

[vladd 26]

if the port is 6" wide there's no reason you can't paint it now. it's a small step but really helps hide a lot of crap. I highly suggest eventually carpeting, if only for the experience

btw for future reference, drywall screws, predrill and use a good quality wood glue like tite bond.

[rushnrun 14]

btw for future reference, drywall screws, predrill and use a good quality wood glue like tite bond.

X2

tite bond works much better than liquid nails, it absorbs into the wood making it "one-piece" the liquid nails is flexible and not really a good choice.

(several people use liquid nails, however, I cannot suggest using it.)

[k_schutte 0]

HHHMMM.... question i guess i should have asked before...

As for carpeting, I have done it several times, which is how i know i don't like doing it ;-)

I am going to have ot rebuild a box later on when i have more time, I should have known better than to listen to the guy at Home Depot. Plus he plain sucks at cutting!! I usualy just have saw horses, a circular saw, square and tape measure and my cuts where way better than what he did on that "stand up table saw" some are up to 1/8" +/- the measurements i told him. I even took time to draw it all out TO SCALE on a piece of graph paper so he knew exactly what cuts to make and everything. I think he just didn't take the width of the blade into account when he made the cuts.

Plus these screws SUCK and are splitting the wood on the corners/ends and when the head hits, instead of sinking in AT ALL, they just spin like hell. He also told me Liquid Nails was a better adhesive then the Tight Bond (which is what i actualy had ot begin with) I am going to have to carpet this box now just to make it presentable. I usualy use an air powered nail gun and Tight Bond but thought this way would actualy be better man was I WRONG!

Oh well, I am going to finish it up and fix it up the best i can for now and get it metered tomorow. Then i will rebuild the box at a later date and see if it might change anythign at all...

[wenn_du_weinst 1]

only thing is I would use wood screws not dry wall screws they hold better

but that may just be for birch I won't use mdf

[- Nickelz N Dimez - 0]

My old box for my 15" Icon is smaller than that and I thought I didnt need any bracing at all. My box flexed so much and the woofer just broke the box down and tore it up.

[Tirefryr 1,742]

only thing is I would use wood screws not dry wall screws they hold better

but that may just be for birch I won't use mdf

Wood screws and drywall screws have the same thread pitch, aside from fine thread drywall screws which are actually better as there is more surface area.

[wenn_du_weinst 1]

they may have the same pitch but the wood screws stick out more into the wood I've blown plenty of boxes apart so I have gotten to test out a bunch of screws

[Tirefryr 1,742]

What do you mean, "they stick out more?"

[k_schutte 0]

So... This was just plain a DISASTER!!! the box turned out like shit! Honestly it is probably worse than the first box i ever built back when i was 15 with partical board and brad nails. Stuff split everywhere, the side of the box the port is on was cut 1" short and in my rage i forgot to put the bracing in. All in all I pretty much wasted $50~ on this box and will probably just put the sub in my old box if it would be OK...

the other box i have is 4ft^3 and tuned to 33hz, double baffle, flush mount, braced and doesn't look near as bad. Only thing that worries me is I am looking for SPL and I don't think that other box being as small and low tuned would give the the desired results! I wish I could find someone local that would build boxes for a decent price... Or atleast someone that knew how to fuckign cut the wood RIGHT so the shit would actualy look decent and more importantly FIT decent.

ANYWAYS, I am going to toss it all in there and see what happens...

[k_schutte 0]

Well, I am happy(ish). Finaly got the sound of my HDC315 back except a little harder IMO... I assume the sound deadening has a lot to do with the lack of flex now still moves a decent amount but nothing like before...

Should be a BEAST when I get my new box and port the rear deck. Once i get the new box I am going to crank teh power up a little more too, Gain is only about 1/3 right now... don't have a DMM anymore to set it so i figure I will leave it for now. HOWEVER if it is that good right now when i get the new box and turn the power up... I CAN"T WAIT!!!

Now i just have to figure out what to do with my rear suspension... Thinking I will airbag the whole car this winter but i don't want to keep scraping/slamming all summer long with all that weight back there....

Edited June 20, 2009 by k_schutte