Slot Port Length

[billb3]

Hi guys,
Just building my first slot ported box for a JL 13W7AE, have tried several different tools to figure out the right port length for a 34.6Hz tune but i can't seem to get the right answer.

If anyone could help it would be greatly appreciated.
Here are the box dimensions i have so far:

Width: 31.5inches (800mm)
Height: 17.4inches (442mm)
Depth: 17.32inches (440mm)

Port Width: 2.2inches (56mm)
Port Height: 16.14inches (410mm)

The box is pretty much built except for the L part of the port, cant seem to calculate the required length.

FYI the 13W7AE driver displacement is 0.21 cu ft / 5.9 L if that helps.

Walls are all 0.63inch(16mm) MDF with front baffle being double 1.26inch(32mm).

Thanks again

[Joe X]

 

Here's a cutsheet detailing how your port needs to be done:

 

Enclosure Specifications:

Fb = 34.6 Hz
Vb = 3.7 ft^3

External Height = 44.2 cm
External Width = 80 cm
External Depth = 44 cm

Port Width = 7 cm

Cut Sheet List:

* All Dimensions in Centimeters.
* Wood Thickness is 1.6 for all Parts.

External Enclosure Parts:

Front = 71.4 x 41
Back = 80 x 41

Left & Right Sides:
Side 1 = 40.8 x 41
Side 2 = 42.4 x 41

Top & Bottom = 80 x 44

L Port Internal Assembly Parts:

Front to Back = 33.8 x 41
Extension = 6.5 x 41

 

 

Bear in mind though that the box is large for that sub so go easy on power and use your subsonic filter to 28Hz.