Box for 18" BL

[stylezzz8o8 0]

wait why is the length for the port only 4? i thought he said 27.25???

The rear portion is 4", the total port length is 27.25"

That box is just under 8 ft^3 tuned to just under 32 Hz. Should work great!

Brian

yeah i didnt know he was talking TOTAL length.

[BKOLFO4 29]

On a side note - I had the RE calc compute port length wrong a couple of times, so I quit using it. . .

It is so easy to make calculations by hand.

1. You know how much net airspace you want.

2. You know how much port area you want.

3. By knowing where the port will be, you can determine the dimensions the port opening needs to be to get the correct port area.

4. Plug in the net volume and port size into a good port length calculator to get the length.

5. Find the port displacement (take into account the port walls).

6. Add the NET volume, driver displacement, and port displacement to get the GROSS volume.

7. Find dimensions for the overall box that will give that gross volume.

When finding overall dimensions, keep in mind the port size you chose.

Also make sure the port does not end up closer to the back wall than the port width. If the distance from the end of the port to the back wall is equal to the port width or smaller, you will have to make adjustments somewhere. . .L shaped port, shorter port, change overall dimensions, etc.