I'm building a port for a fibreglass sub box,and to fit it in the box, I have made it curved. The port area is 5" x 3.25", curved around the narrow side, with about a 2 ft radius ( about the shape of a section of a tire).
The question is how to shape the ends of the port?
Should they be tangential to the port, or angled to account for the different lengths of the inside and outside of the curve? Average port length is 19"....about 16" on the inside curve, 22 on the outside.
Sorry no pics yet.

[ March 19, 2005, 11:51 AM: Message edited by: Car Trek ]

 

Try to keep the port away from cabinet walls, flaring the port on both ends is ideal.
Look at Aeroports .

 

I had to make these ports myself outa fibreglass in order to fit the box. Yes they are quite flared at both ends.
I've talked to a few knowledgable people, and read as much as I could find, and the concensus seems to be that an angled end will not sound appreciably different than a 90 degree end.
I'd think that an angled end would give a slightly wider parabola, that could perhaps be measured, but whether or not it would be a benefit or detriment, would depend on each application.
Now I'm sure my sig will be appropriate!!!