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DiamondPoint
10-06-2013, 03:49 AM
So I was wondering does anyone know any good lessons on ported box, like to find displacement, tuning and crap like that. I want to widen my knowledge on it. Like what's the effect of adding support beams to a box, does it mess with the tuning of a box, and do I subtract or add displacement from subwoofer and support beams to the cubic feet of a box? Like that type of knowledge.

bbeljefe
10-06-2013, 01:08 PM
There are a number of websites that explain enclosure design. Basic Car Audio Electronics (http://www.bcae1.com/) and DIY Subwoofers (http://www.diysubwoofers.org/) are both good. I know BCAE has a port calculator but I'm not sure about the latter.

As for volumes of ports, braces and drivers, they must all be add to the net volume you're looking for. So for instance, if you calculate a 1 cube box with 30Hz tuning, you'll need to add the displacement of the driver, port and any bracing you may need. That'll usually push the box size up to 1.5-1.75 cubes depending on the driver size and port type/length.

A good rule of thumb when selecting a box type is efficiency bandwidth product (EBP). This value is derived from dividing driver Fs by Qes. Drivers below 50 generally do better in sealed or 4th order boxes, those between 50 & 75 do well in both and those above 75 do best in ported or 6th order boxes. Moreover, drivers with a low EBP will require larger ported boxes in order to yield a flat response while those with high EBP will perform well in smaller ported enclosures.

DiamondPoint
10-06-2013, 04:06 PM
There are a number of websites that explain enclosure design. Basic Car Audio Electronics (http://www.bcae1.com/) and DIY Subwoofers (http://www.diysubwoofers.org/) are both good. I know BCAE has a port calculator but I'm not sure about the latter.

As for volumes of ports, braces and drivers, they must all be add to the net volume you're looking for. So for instance, if you calculate a 1 cube box with 30Hz tuning, you'll need to add the displacement of the driver, port and any bracing you may need. That'll usually push the box size up to 1.5-1.75 cubes depending on the driver size and port type/length.

A good rule of thumb when selecting a box type is efficiency bandwidth product (EBP). This value is derived from dividing driver Fs by Qes. Drivers below 50 generally do better in sealed or 4th order boxes, those between 50 & 75 do well in both and those above 75 do best in ported or 6th order boxes. Moreover, drivers with a low EBP will require larger ported boxes in order to yield a flat response while those with high EBP will perform well in smaller ported enclosures.
Thank you so much brotha, this helps me a lot. I honestly didn't know any of that, I just thought you could throw a sub into whatever you want and get away with it xD haha now I know a little more :)