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dtp
01-12-2008, 01:05 PM
i don't know how to ask but i will try to explain
i was looking at Moe Lester box designs and tried to work it out using
http://www.bcae1.com/spboxnew2.htm
but it did not work out in respect to cubic ft posted to be 2.0cuft tuned at 31hz
use this design for example http://img62.imageshack.us/my.php?image=2cubes31hz2925sqin4kn.png
i notice that the port volume was not included
just the internal volume was used to make up 2.0cuft (1.64 + .54)cuft
so question is should i follow this pattern excluding the port volume or should the port volume and internal volume should add up to total 2.0cuft
and i am not trying to diss moe lester designs

Immacomputer
01-12-2008, 04:23 PM
You're looking at net volume vs gross volume. Gross volume is only useful in deciding if you have enough room to put a certain size box in... that's all it's good for. Net volume is what matters and should be the only volume you're concerned with as far as what size the enclosure is.

http://i7.tinypic.com/6z9rwn9.png

The green is NET area and the orange is GROSS area. When you multiply by the height, you get net and gross volume.

dtp
01-12-2008, 05:20 PM
ok this their a online calculator to calculate the port length given the cuft
http://www.bcae1.com/spboxnew2.htm
using this calculator what this means ( Sq. Port Ratio H:W?)
what the 1:1/1:0.5/1:2 means how to use this