building a sub box

[Sully72]

Has anyone here built there own sub box ? I just bought a 12 inch JVC sub and im not sure what size to make the box , if someone would like to measure there sub box for me , this would be a great help . thanks .

 

[Julie]

I have built a sub box b4, 3 seperate ones for rf 12" subs. However my measurements won't help you any, as it is a very custom design.

Best bet is to:

A. decide whther you want a ported or sealed enclosure.
B. look up the recommended volume (litres) required for the sub in ported/ sealed form.
C.Down load the sub box calculator from www.caraudioaustralia.com.au, (if they still have it- I downloaded it a couple of years ago so I'm not sure. Or you could come up with a rough design and rough sizes you would like, and use the old maths u learnt in school and never thought u would need and work out the volume and then adjust the sizes according until you come up with something desirable.

or you could just hope that someone has made a box for this particular sub, and is willing to post dimensions :unsure:

 

[clinker1212]

Yeah, the dimensions are different for each application. You could work on the below as a bit of a guide

Driver Diameter Vol of enclosure
Inches Feet 3
6 .3-.4
8 .6-.8
10 1-1.5
12 2. - 3.
15 5. - 9.

So you are looking at about two to three cubic feet for each driver. What you need to do is work out a rough design for it to fit into your boot. Then work out the cubic feet from that (this can get quite messy depending on where you want it). I found that the best way was to use some cardboard to cut out a rough shape of the sides first.

If you are going to get into it then I found these sites really interesting: There are plenty of guides and info sites on this.

http://www.diysubwoofers.org/faq.htm
http://www.the12volt.com/caraudio/boxes.asp

Have a bit of a search.

If not- it is more then likely that some mob has made suitable shaped boxes for your particular application and go and buy one (This may actually work out possibly cheaper and far less effort if you don't have the equipment etc.).

 

[Jeff]

If you want it to work properly it needs to be designed to suit the speaker and available space. Send me the speaker (full) details as per the Thiele/Small guidelines and the dimensions of the space it has to fit and I will tell you if it is worth using. If so, then I could do a design for the box. if you don't have the full speaker parameters give me the model number and any details from the nameplate.
if you want decent bass in a vehicle then a ported box is the only way to go but all dimensions are critical for best results and copying someone else's box will probably not work unless;
-they have the same driver,
-they have the same vehicle
-their box was properly designed in the first place.
Even a mm or two difference in some dimensions can make a big difference.

 

[KAL SPL]

40L sealed box is the best bet.
300 x 300 x 450 or there abouts

 

[Sully72]

Ok it's one, JVC model number CSD-3000 12 inch 600 watt sub , going into the VS Statesman . I want to put it in the boot where the cd stacker was ( right hand side of boot ) I was thinking about a wedge box as I need boot space, the guys at Tonkin car audio said that one of there wedge boxes would work fine but they cost more than the sub, thanks heaps .

 

[clinker1212]

Question for Jeff

Hi Jeff

I have heard two different theories about what the dimensions should be of a box. One is that neither the hieght, length and depth should be the same distance. Another is that the height should be 1.7 times the width and the depth should be .7 times the width.

Does any of this make much of a difference? What is best?
I just want to know cause if you want to save some boot space the shape is not going to be that of a standard rect prism with 90 degree angles lol. Especially if you are struggling to get enough volume.

Also I agree that ported is the way to go unless you are getting multiple drivers and have a mixture of sealed and ported.

Hey-- I just got off the phone to A car audio mob who are selling 12" poineer subs 350watt RMS for $90 a pop while stocks last. I've got a poineer MP3 player.. what are their subs like?

 

[KAL SPL]

If they have model number 305c then there awsome subs.
Very large magnet and built good.

 

[clinker1212]

Sweet!

Yeah I just bought two. And I also got a quote for a dual enclosure to suit the car and subs @ $179.00 . Can't go wrong cheaper then trying to build one almost.

Now the more expensive part will be getting a suitable amp. There is a 4 channel bridgable pioneer that will run 300watts on two channels- would this be suitable?

I also want to get component speakers for the front as I am still using the factories in my VS. Any ideas on where to mount the tweeters?

thanks

 

[clinker1212]

Ok it's one, JVC model number CSD-3000 12 inch 600 watt sub , going into the VS Statesman . I want to put it in the boot where the cd stacker was ( right hand side of boot ) I was thinking about a wedge box as I need boot space, the guys at Tonkin car audio said that one of there wedge boxes would work fine but they cost more than the sub, thanks heaps .

If you havent had much experience with this kind of thing, I would strongly advise shopping around and getting heaps of info on it before braving the task yourself.

Tally up the costs of materials and your time against that of the box you can buy. You can't make any mistakes with the box either. Has to be air tight (apart from the port), built out of the right stuff, braced correctly and the right size/ volume. At least you can steal the dimensions off of the commercial design. But then you need to cut your materials to the required sizes and angles. Pretty hard for a first time attempt.