Re: Help with my car audio [message #25463 is a reply to message #25453] |
Mon, 08 October 2007 01:07 |
|
Wayne Parham
Messages: 18792 Registered: January 2001
|
Illuminati (33rd Degree) |
|
|
Well, in layman's terms, the formula that predicts the frequency a box is tuned for assumes a straight port, not one that is bent or flared or made into a "T" shape. Those kinds of changes are straightforward, and a finite element analysis could surely be done which would give a very accurate frequency prediction. But the Helmholtz formula assumes a straight port, so if you deviate from that too much, the formula will become inaccurate. When making an unusually shaped port, you can always estimate, make the port how long you think it should be and then measure it and modify as needed. Best to make it long at first, that way you can trim it down to size to get the desired frequency.
|
|
|