Trying to make something

onewickedkid05 · Post by **onewickedkid05** » Sat May 31, 2008 11:27 pm

I have a good question. I have been contimplating making a sub box for a while now. And since i cant seem to sell my two twelve inch subs i guess ill use them. I want to try and make a box that doenst take up all my trunk space so i was thinkin of something like this

http://cgi.ebay.com/ebaymotors/Custom-N ... enameZWD1V

Except instead of paying 160 bucks i would just make it myself

Any ideas on what would be the Lightest most durable material i could use. I want to basically build it like that but i was gonna try doing mine on a slight backward angle so they aimed towards the rear seats slightly
I also want to put the amp right inbetween the two subs?

What should i build the frame out of
What should i use as the main boards

Any specific types of screws i need

Any help with stuff to buy and where to buy it and how to get the best quality one made would be appreciated.

AND NO i dont want to use fiberglass lol

jT · Post by jT » Sat May 31, 2008 11:50 pm

cant help you on the supplies but building a box isnt just about materials.. you need to build it to specifications for the subs.. interior cubic feet, etc .. and with 2 subs you should probably have to have separate sealed compartments (each one properly spec'd for the sub) otherwise they will interfere with each other

its a lot of work to do it properly... that is, if you care about doing it properly.. otherwise just get some particle board or plywood and build a rectangle box with 2 holes cut out.

onewickedkid05 · Post by **onewickedkid05** » Sun Jun 01, 2008 12:34 am

i want it to look like the one in the link i posted

NiteHawk · Post by **NiteHawk** » Sun Jun 01, 2008 12:53 am

i'de like to know how in the hell they even get those things IN the trunk in the first place.....

thanks for the idea though

onewickedkid05 · Post by **onewickedkid05** » Sun Jun 01, 2008 1:04 am

your welcome lol....i have no idea how they got it in there but i want to do the same thing but i want to seal off each sub in there own section.and fill that section with stuffing......im not reallli that knowldegable about subs and specs and stuff so any info would really help

Subs: 2 12" earthquake DBs 600watts rms

jT · Post by jT » Sun Jun 01, 2008 2:15 am

the only info i found was this

DB-12
- 600 MAX
- Fs = 27Hz
- Qts = 0.6339
- Vas = 3.19 cubic ft
- Sen = 90dB
- 2" polymide coil (4 ohms)
- 50 Oz magnet
- Santoprene surround

so each section of the box would have to be built with an internal size of 3.19 cubic ft of air/space..

just google how to build sub boxes

Jeremy M · Post by **Jeremy M** » Sun Jun 01, 2008 3:29 am

ok first off you'll need:

birch is the lightest wood, and it's stronger then MDF. (u want 3/4")

i use drywall screwes and make sure you pre-drill.

you'll need some wood glue, i've been using gorilla glue, but i see alot of people using TiteBond II.

depending on where u live, Home depot, Lowes, etc etc is where u can find the materials u need.

are u skilled with a table saw or would u need to have the cuts done for you?

onewickedkid05 · Post by **onewickedkid05** » Sun Jun 01, 2008 10:12 am

Im not SKILLED at a table saw nor do i own one. But im not dumb lol

nineball · Post by **nineball** » Sun Jun 01, 2008 11:29 am

jT wrote: .. and with 2 subs you should probably have to have separate sealed compartments (each one properly spec'd for the sub) otherwise they will interfere with each other

not true at all. there is no problem with shared airspace so long as it has the proper dimensions.

jT · Post by jT » Sun Jun 01, 2008 11:43 am

For multiple-driver enclosures, you'll get the best performance by isolating each driver in a separate chamber. This prevents variations in speaker tolerances and input power from restricting system output. If building separate chambers isn't feasible, you can make sure that each driver receives the same amount of power by mounting two identical drivers in the same cavity and wiring them in parallel.

thats just the first quote i pulled up... thats what i had always heard too... just for the "best" performance. but i'm no expert..

http://www.google.com/search?q=build+sub+box

theres a few pages of good info for your basic construction..

NiteHawk · Post by **NiteHawk** » Sun Jun 01, 2008 5:10 pm

jT wrote:the only info i found was this

DB-12
- 600 MAX
- Fs = 27Hz
- Qts = 0.6339
- Vas = 3.19 cubic ft
- Sen = 90dB
- 2" polymide coil (4 ohms)
- 50 Oz magnet
- Santoprene surround

so each section of the box would have to be built with an internal size of 3.19 cubic ft of air/space..

just google how to build sub boxes

your way off on the space requirements there bro...

Vas is, be definition:

"Equivalent volume of compliance", this is a volume of air whose compliance is the same as a driver's acoustical compliance Cms (q.v.), in cubic meters. "Vas represents the volume of air that when compressed to one cubic meter exerts the same force as the compliance (Cms) of the suspension in a particular speaker. Vas is one of the trickiest parameters to measure because air pressure changes relative to humidity and temperature — a precisely controlled lab environment is essential. Cms is measured in meters per Newton. Cms is the force exerted by the mechanical suspension of the speaker. It is simply a measurement of its stiffness. Considering stiffness (Cms), in conjunction with the Q parameters gives rise to the kind of subjective decisions made by car manufacturers when tuning cars between comfort to carry the president and precision to go racing. Think of the peaks and valleys of audio signals like a road surface then consider that the ideal speaker suspension is like car suspension that can traverse the rockiest terrain with race-car precision and sensitivity at the speed of a fighter plane. It’s quite a challenge because focusing on any one discipline tends to have a detrimental effect on the others. "

Vas has nothing to do with recommended enclosure size.

i'm not the manufacturer, so i cant say for sure what the recommended size is for your subs, but here's a couple i threw together real quick, this will give you an idea what the response curves will be like with a 2cubic sealed box and a 3cubic ported box...

the ported box hands down has the sealed box beat, with much more low end bass...

Jeremy M · Post by **Jeremy M** » Mon Jun 02, 2008 12:41 am

the only real advantage to putting the subs into seperate sealed chambers is to save on space....but if u blow a sub chances are u might not tell w/o pulling the sub out, cuz the air pressure in a common chamber will move the bad sub still.

NiteHawk · Post by **NiteHawk** » Mon Jun 02, 2008 1:26 am

actually, it is smarter to have seperate sealed chambers inside of a single box for multiple subs. Having seperate chambers will prevent the subs from fighting against each other if they're not both being given the same amount of power (for instance, wired in stereo). Also, if you have a single chamber for multiple, and 1 sub goes, it continues to move like as if nothing was wrong, which puts more stress on the good subwoofer.

there are some more technical reasons why seperate chambers is better, but none of those reasons are of that big a concern, since I doubt you're planning on entering SQ competitions.

Themaggots · Post by **Themaggots** » Mon Jun 02, 2008 4:02 am

http://spkrbox1.spaces.live.com/

Read this. It answered a lot of my questions when I built my sub boxes.