Sub box
 

Bought a 10' sub (thanks frank) for the 4runner and am tryin ta decide what exactly I wanna do with it. Im taking out a 8' bazooka tube sub, that took up no space, and would like to try to do that again. Was thinkin of tryin to make a box, similar to blizzards (https://www.yotatech.com/forums/f96/my-audio-install-90001/), but was not sure what was the best material to build the box with. Ive seen a couple different things and was wonderin if one was any better than the other. My amp (from the bazooka) is in the drivers side rear cargo area, so wiring is no problem. Thanks for any help.

The best material to make ANY sub box out of is 3/4 inch MDF (Medium Density Fiberboard)... Unless you have skills with Fiberglass which is difficult to work with can be very messy. I competed systems for a living for 10 years, and there really isn't anything that will sound better than 3/4 inch MDF.

Blizzard states his box is made from "DM" wood which is exactly the same thing as MDF

A TEN FOOT Sub?!!!! holy crap!!

haha oooooooooooopsssss

same as lofreqjeff posted above.... MDF is the way to go

I want a 10' sub too! lol


MDF is the nice cheap way to go....but if you dont mind dropping 70+ bux for a single 4'x8'x1" sheet of void-free 9ply birch, it will do quite a bit better than MDF as it is far more rigid yet equally as dense!

Personally, Ill stick to MDF at 20bux a sheet for 4'x8'x3/4" and reinforce it with fiberglass at 30 bux a gallon which is more than enough to cover a few dozen boxes...hehe


since you are new to boxes, MDF (Medium Density Firberboard), sometimes labeled incorrectly HDF is typically used. A single 4'x8'x3/4" sheet will tip the scales at around 95-110lbs pending its density. Building a box with it dictates that you use good wood glue (elmers probond for me) with #8 coarse thread 1-5/8" drywall screws to hold everything inplace until the glue dries. Keep all screws 4"+ away from ends or else you will have a visible split on the end of a panel.

Once box is done, coatingthe interior with fiberglass resin is a great idea to seal it up and fill any open voids that may be there from imprefection in cutting.

A table saw is invaluable, but using c clamps, some 60" long angle iron, and a circular saw, its still easy to cut perfectly straight lines too.

As far as covering, Ive foundthat the 3M Hi Tack 90 is by far the best spray adhesive ive ever used. But at 14 bux a can it damn well better be! Carpet for the box, I'd generally stick to a cabinet based carpet. These carpets tned to be tough yet still strechable! :D

Steve

Since you're asking i assume this is your time building a box. In that case, skip the MDF. It is better but for a first timer its too hard to work with plus if it ever gets wet it swells up and is ruined. Stick with plain old pine 3/4'' plywood from the DIY mart, it's worth the extra money to have the build go smoothly. And i doubt you'll hear the between the plywood and the MDF.

No offense intended, but are you nuts?!?!:spank: :chair:

Plain ole 3/4" ply wood is HARDER to work with than MDF (ever see the crap split even when cut with a finishing blade??), is not void free which WILL give you rattles right off the bat, becasue of it's somewhat solid nature will not seal very well, and is just a slipshod way to build a box.

MDF is just fine and is what every beginer should use.

25+ 1st place finishes in competition dont lie....

Oh and yes you can hear the difference btwn the two, main difference being is that regular old plywood will rattle like mad.

Yeah MDF is definitely the way to go. I've used it for all the boxes i've built (10+). I built my first box by myself using it and didnt have any problems, although like said above, watch the water. If you do get it wet it's ruined. so just keep it dryin and get it sealed and carpeted and you wont have any problems.

I have never had any of my plywood boxes rattle in any way. You must have experienced poor craftmanship. As far as the "splitting" issue, I assume you're talking about splintering. If you get splintering then you're cutting too fast, plus I'd rather deal with a little splintering than the toxic dust cloud that cutting MDF creates. And the pieces won't break if mishandled.

The part about plywood being too solid to seal I just dont understand. All the joints should be glued on assembly and the corners should be caulked on the inside before the speakers are installed. I don't see how this wouldn't seal.

I'm not trying to get in an arguement here, but if I'm going to build the box I prefer to use plywood. If I'm paying someone to build the box, they can use whatever the want. Besides, I guarantee that if plywood were cheaper than MDF, every stereo shop in the country would use it for thier customer cars.

Brick - sorry about the opening salvo on that last post, I was having a bad day and inadvertantly took it out on you.

But I have never used ply wood, nor would I buy a plywood built box if I didnt make my own. From my own experience, splintering happens all the time with any blade you use, at any speed. over the years I've used rip blades, finishing blades, hardwood blades... Trust me, we build storm shutters every year out of tounge and groove 1" for hurricane season! (ugg hurricane season again...) and no matter how slow ya cut it, the top layer nearest the blade is always splintered. Then you have the splitting issues. Even after countersinking, running a drywall screw into one end of it will induce delamination, and eventually, rattling. MDF doesnt do this when properly countersunk, screwed, and glued.

As far as rattling is concerned, that happens over time with standard plywood. This comes by the flexion in the panels every time the sub hit. This flexion severely stresses the glue btwn the laminations as well as the wood itslef, and over time you again get delamination and breakin of the wood, and then wood starts slapping and you get rattling. At first, ply may work, but given time, they will start. ;)

Yes MDF is very toxic, but all ya gotta do is hook up the vacuum to the table saw and then router and wola, no dust of any kind! :D Now for a newbie, a nice cheapy facemask works wonders too. (I also recommend eye and ear protection!! Some cheapy sunglasses ya got bouncing around, and 6 sets of wally world 1.99 ear plugs go long way! :) )

MDF aint that cheap here - 22 bux as sheet stinks! And cheaper still is LDF and particle board they use for housing. Of all the shops I've been to in the state and country for that matter, they all use MDF. IMO it aint because its the cheapest... ;)

OK i did some poking around online at my local Home depot.

MDF for a 3/4" 4x8 sheet is 21.95 per board
OSB Particle of the same dimenstions is 17 and change
Standard Ply wood was 19.95

Thats a 2 dollar difference and since shops buy the stuff a pallate at a time 2bux * 30+ (or however much is in a pallate) that adds up quick...

Never heard of plywood sub boxes... only MDF, which is really not hard to work with. And if you are worried about water issues, just coat the outside in fiberglass resin and sand smooth. Voila... waterproof and sealed on the outside as well.

Just my dos pesos...

MDF is the way to go. I built a plywoood box when I first got into the car audio scene and didn't know any better. Now that I know better, I leave the plywood for roof sheathing...

A few facts about MDF. Lower resonant frequency due to it's density and it machines like a dream. Plywood can't compare. Like coming to a gun fight with a knife...