Enclosure Calculations

[caintrain 0]

When Calculating port length, How can you enter the box volume after port displacement, without knowing what the port length will be. Or do you put in what you want your box to be after the displacements and then design a box that takes this into account. For example, if you want a box to be 4.5 cuft. after displacements you would use this to calculate the port length. Then after you have that you would calculate the port displacement lets say is .5 , SO you would do .5 + 4.5 to get 5 cuft., then design a box that is five cuft before port displacement and use the port length that was calculated to get the desired tuning?

If someone needs further explanation please ask.

Thanks.

[cubdenno 0]

When Calculating port length, How can you enter the box volume after port displacement, without knowing what the port length will be. Or do you put in what you want your box to be after the displacements and then design a box that takes this into account. For example, if you want a box to be 4.5 cuft. after displacements you would use this to calculate the port length. Then after you have that you would calculate the port displacement lets say is .5 , SO you would do .5 + 4.5 to get 5 cuft., then design a box that is five cuft before port displacement and use the port length that was calculated to get the desired tuning?

If someone needs further explanation please ask.

Thanks.

Yes.

I use WinISD initially to model enclosures first. When I determine that the response and space are something that I can live with, I simply figure the volume of the enclosure and add in the volume of the port. I use another program I got from a link on this site. Unfortunately it's on my home PC. I can send it to you later. It does the volume displacement calculations for you. plus lets you know about potential resonances. I use both that and WinISD and Unibox. It's a lot of trial and error, but no less than using something like AKABAK with way less of a learning curve.