ZpEeDRaCeR

Would save alot of time and effort i assemble a box out of wood and then fiberglass the inside and outside, rathe than trying to build it straight from glass using no wood? would have the same strength/performance?

macka

IMO, if you build it out of wood, then why would you glass it, there really is no need (just use 3/4 MDF and you will be fine).

The only real reason to use glass is if you have a shape that is not easly cut or made out of wood (kick plates for example).

If you like the look of glass, do what I did (actually am doing right now). I built the box out of wood, but the face that holds the subs is glass because I wanted that shiny look.

ZpEeDRaCeR

ya i think that is what i will do, what is MDF?
a type of wood? can i spray paint it and get it to look anywhere halfway descent or do i have to spend money at a shop to paint it?

macka

mdf is a type of wood, just go to Lowes or Home Depot and ask, they will know what you want. Make sure to get 3/4 inch or your box might be to flimsy.

As for paining it, I suppose with the right tools you could get is to look good. Sand it with AT LEAST 120 grit sand paper to get it smooth. I would primer it twice, then paint in twice then at least 2 coats of clear. That should give you an OK shine. You might try a glossy type paint, that will help.

alphared

Man, I would suggest you do a bit more research before making the sub box. I mean if you didn't know what MDF was, can't imagine you making a box that works. depending on size, you'll need bracing. Have to make it air tight. You can paint MDF, but its so porous that it won't look good (unless you know what your doing). Sanding it won't change anything since the result is still bumpy (its just compressed sawdust) You gonna have to cover it with carpet or vinyl.

macka

I respectfully disagree alphared, you can paint MDF. You just have to prime it twice like I said (after you sand it with a VERY VERY FINE sandpaper to get all of the "bumps" and lines out). I have seen (and made) alot of stuff that is painted MDF and it looks good if you do it correctly.

As for Zpeedracer not knowing, I say what the hell, you have to learn somehow right. I mean none of us just all of a sudden knew how to make a box and what to do, you had to learn it some how, some way, and at least zpeedracer is asking. Most people won't even do that, they would rather build a crappy box and wonder why their 10w7's (et al) suck!

ZpEeDRaCeR

heck ya! thanks for the support macka. i still might decide to let a local stereo shop fiberglass it after i build if i doint paint it. also, how and where do i make a hole for the amp and sub to be connected? i saw in someone's custom fiberglass boq they cut a circle for terminals.

ZpEeDRaCeR

besides alphared if it comes out like shyte i can always have one prof. made.

macka

ZR,

The subs are connected to the amp via speaker wire. So you only need to mount a pos/neg post to the side of the box ( you might want one or two depending on how you wire your speakers). You can find these at ANY place that sells car speakers. The are usually black and round with a red(+) and black (-) clip (unless you buy a really nice one then it will have two gold post on it).

I think this is what you are asking right?

Or are you asking how to physically attach the amp(s) to the box that you build (i.e an amp rack)?

ZpEeDRaCeR

no that is what i was asking, thank i just bout one with the gold posts for $8.

Hencho

iTrader: (1)

It depends if you want to remove the box a lot or not - i usually just dril a hole small enough to fit the speaker wire through, then use liquid nails to seal the hole i made.

also instead of fiberglassing to make sure its sealed just run beads of caulk / liquid nails around all of the edges.

car audio is much easier than it seems - the hardest part is figuring out how big of a box / what dimensions you have to make for youre sub.

ZpEeDRaCeR

ok, i bought the wood and some wood glue and screws incase it needs more support a saw and sandpaper for adjustments. and silcone to caulk it. final i was surprised to see primer paint and clearcoat are all available in spray paint. will start after the holiday

alphared

whoa, just jump on me why don't yah
I never said you can't paint MDF.

I also said that he should do more research before building it. I'm all for DIY, but you can't just jump right into something you've never done with checking all possible info. (and reading this i'm still sticking to my first post)

I suggest pro because Zpeedracer ask if it would save time and energy to make it himself, and no, a pro would save time and energy. I mean if the box turns out like crap Zpeedracer is gonna get a box made by a pro. Why no save the money and get it pro made in the first place, save time and frustration.

well good luck to yah Zpeedracer, post pics when your done

macka

Sorry alphared, I didn't mean for my post to sound like I was jumping you. I was just trying to show how it is a good thing that he is trying and wanting to learn.

To me, building the stuff is half the fun of a system. I have been doing my install for three days and have loved every last minute of it (except the 153 times I have cut my hand (man the Z is like a computer case(you IT guys know what I mean))) <--that is a lot of parenth's

Anyway, sorry alphared, and good luck zpeedracer!

bastard

I would seriously recommend researching this before beginning. It's not that difficult to make a good sealed box as long as it's completely airtight, well braced (any flex will eat your output) and within about 5-10% of the recommended airspace. Don't forget you have to add the speaker's displacement to the recommended airspace. A ported, or worse yet, bandpass box requires much more work and is a lot harder to calculate.

Ported requires the calculation of the box volume and the length and diameter of the port. Bandpass is similar but requires two enclosures and a port. The bandpass is the least tolerant of miscalculations of these 3 designs.

In my estimation, the sealed box is the best deal: Easiest to construct, and (I think) it sounds the best. Now, if I recall correctly, the width of the area under the strut bar is around 3 feet, so this will require bracing. Braces can be made out of strips of MDF glued together like a square, or you can just use a sheet of MDF with big holes drilled in it. Don't forget you have to subtract the volume lost to the braces from the enclosure volume--it's simpler to use strips of MDF for bracing because of this: It turns it into a simple LxWxH formula instead of some pi silliness.

Remember also: one cubic foot is 1728 cubic inches (12x12x12).

ZpEeDRaCeR

actually, even though i am a virgin installer i have been reading how to's on this forum like an insomniac for about two weeks, i feel pretgty confident, espicially since i got out of the fiberglass route, and will began after turkeyday. i will post pics as i go too.
Thanx for all the support!
~Zpeedracer