Can port on enclosure be anywhere?

Question

From my understanding, the port on an enclosure can be just about anywhere, as long as it is on the same face as the subwoofer. Does that mean basically just the length of the port and the diameter of the port will affect the way the sub sounds, and not where on the face it is (meaning how close or far it is from the subwoofer)?

Also, how do you determine what frequency you want to tune the port to? or is it always 37 hertz?

Thanks for the help!

Answer 1

I'd venture that port location primarily depends on the internal characteristics of the speaker - for example, my boss has some Logitech desk speakers for his laptop and while they're not great quality, they do the job - but the port is on the top of the speaker units (with the drivers themselves facing front at the top (!) of the enclosure. The tweeters are underneath the woofers.

Don't ask why, they're slightly 'odd' things.

My Vibe sub has its port on the front, quite standard really - I think it probably just keeps manufacture and design costs down without compromising on performance. However, I wouldn't just aim for a tuned freq of 37Hz - there's some fiddly calculations you have to work out when you're manufacturing your enclosure/cab depending on the characteristics of the driver(s) you're using, most of which are far beyond my comprehension (I've helped make a couple of ported subs but I was working with someone - and they did all the maths!)

There are some very useful pages on the web that might help you get cracking (including some calculators where you just feed in the relevant info and it spits out the optimal values for you) - I linked a relevant Google results page, so check those out, then find a friend who's good with soundsystems ;)

I wish you the very best of luck! Once you get cracking, there's something quite rewarding about building your own speakers.

Answer 2

Tuning frequency and box size/type depends on speaker parameters. Not all subs can play nice with basreflex, not all can play in sealed box. But speaker and acoustics is not so strict in the way like "35litre box will play nice and 36 won't..." you have some choice to decide, if you want to push it to play more loud, more exact, more deep. By changing this, you changing some parameters like maximal power handling, distortion by Group delay effect and many more. so You have to choose the speaker which can handle your needs, and than build it with some compromise between speaker abilities and your taste. If you don't know how, manufacturer does instead of you. But how can they know whats best for you? They don't, they try to make it most universal.

Answer 3

no you cannot just put it anywhere, just like the size and length of the port determine the tuning (sound) so does the location and shape of the port, if you are not experienced or don't have a good program to help you, you would be better off buying a prefab box with the correct volume (cu.ft.)

Answer 4

It can't be "anywhere" but pretty close to it.  As long as the port is unobstructed on the ends it will not really matter.  If you are using a round port then put it at least diameter's length away from all sides.  

You can actually have a port on pretty much any side of the enclosure you choose.  Having it on the same side as the sub is usually the best and most convenient.  However, you can put it on the side, back, top, pretty much anywhere.  The only real problems you would encounter is if the port was obstructed and firing straight into a seat or something.  Also, you must keep the port within a couple of feet from the sub.  Other then that you can put it where you want.

The tuning frequency of your enclosure is based on the port's length, cross sectional area, and the internal volume of the enclosure (not including the port, sub or bracing).  Usually it is best to design the enclosure around the port.  For round ports if you know the displacement then you can just account for that in the size of the enclosure though.  

You can have any number tuning frequency.  37Hz is not the only frequency.  A frequency like that is not going to be the best for all subs.  What tuning frequency you choose should be based on the manufacturer's recommendations.  That will be the best indication of what tuning frequency will work the best for your sub.

Good Luck!!!