Slot port. Using cabinet walls. How to correct? Help!

[tarnationsauce]

I am making a subwoofer with a slot vent. It will be using the bottom and sides as part of the vent. I know that a speaker box calculator will show how long a vent should be if it's a regular vent, but with 3 out of 4 of the vents walls continuing past the port, It must be tuned lower and there must be a way to correct it.
I made a pic to demonstrate what I mean.





The finished product will look something kind of like this:

[BassAwdyO]

if your tuning is below 40hz and the length of your vent is over 12 inches.... dont worry too much about being Dead on accurate... you wont really be able to hear much difference anyhow unless the tuning changes by more than 5hz or so

[simon5]

The method is usually to add half of the heigth distance to your length, you will have the effective length.

Look on this page, near the end.

http://www.jlaudio.com/tutorials/ports/index.html

[tarnationsauce]

Thanks, That's just waht I needed.