# how to calculate interior Volume

Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=34083
Printed Date: November 30, 2022 at 10:55 AM

Topic: how to calculate interior Volume

Posted By: Mjbarahona
Subject: how to calculate interior Volume
Date Posted: June 17, 2004 at 6:17 PM

Hey guys, i'm doing a fiberglass box for an 1985 4runner on its rear side, but i dont know how to accurately calculate the interior volume since the box's shape is not even on the sides. if i have two JL audio w3v2 and they requier .60-.90 Cubic feet of air each, does it mean that i need a total 1.20 cufeet - 1.80 cufeet for both subs? Any assistance will be appreciated.

Replies:

Posted By: Teamrf
Date Posted: June 17, 2004 at 6:55 PM
What kind of material are you using for the fiberglass?

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Posted By: forbidden
Date Posted: June 17, 2004 at 8:14 PM

The combined volume of the box should fall between 1.2 - 1.8 cu.ft. in total. I would edge towards the larger side for better performance. If you are using a mono amp, the subs can be in a common chamber. If you are running the subs in stereo it is best to put the subs in separate enclosures. If you are going to build a mono chamber box, at least include some kind of center brace into it as well to keep the box from flexing.

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Posted By: icu400
Date Posted: June 17, 2004 at 8:33 PM
I would say divide the two halves if possible; i helped my friend install 2 JL w0's in a box that was not divided and then we put a divider in the middle and it sounded tons better.

As far as measuring goes, you could over estimate it and aim for .9 each side and then you should fall around .75-.8 which will work fine. Its pretty tricky to measure odd shaped areas. You could also measure small pieces one at a time and add that together. Hope that helps.

Posted By: jaymes
Date Posted: June 17, 2004 at 8:39 PM
you can get any packign material like foam pieces or peanuts and fill the enclosure with that and measure how much space they take up in a shoe box. U could even use sand. Make it bigger and if its to big you can screw some wood down inside to make up for the space