View Full Version : Difference between slot and square/rectangular port

11-25-2013, 05:50 PM
Can somebody tell me the difference between a slot and square/rectangular port? I can't find a straight answer. I've read there is no difference, that a slot port can being "floating" in the middle of the box like a square/rectangular port and I've read that for it to be a slot port is has to use a wall of the box as a wall of the port.

Side Show
11-25-2013, 11:14 PM

11-25-2013, 11:45 PM
Slot port is the word used to differentiate between square or rectangular ports and round ports. A square is not technically a slot but a slot is also not necessarily a rectangle, but we're not concerned with that level of accuracy in these descriptions.

Why are you wondering?

11-26-2013, 01:33 AM
Mostly just curious. But also on a box/port calculator on carstereo.com first it asks if its round or square port then it asks if its a slot port. So if square and slot are the same that makes no sense

11-26-2013, 01:52 AM
It has to do with port velocity but there are also other things to consider so yeah, I tend to agree with you there. Not that it makes no sense but, that it's not of much relevance.

After all, our ears do well to discern a difference between 30Hz and 34Hz (most people's, at least) so a slight variation in port velocity is not an issue. But, that calculator is based on mathematics and mathematics is an exact science so... the author decided to take that into consideration even though it's not really relevant.

11-26-2013, 03:16 AM
My "guess" would be it considers a slot port to be using one exterior wall of the enclosure and uses an end correction factor when calculating port length...

11-26-2013, 01:37 PM
If you are calculating a complete box then, round, square, rectangle and slot are all different. If you are confined by space, a slot port would be ideal as you will be adding less material to the inside of the box that would affect your volume. If you have plent of space the other three would be fine since you can expand the size of the box to make up for volume lost to the port walls.