dual ported, single port, blah blah blah

[SkinnyBoy]

basically, what would be the results on this design box? as opposed to having a divider between the ports? also, what would be the result if only one woofer was driven? its going in a car, and having a divider would look ugly. THANX!!!

[johninCR]

That will work but you need to have the 2 port combine more fluidly like with a divider at the initial junction of the ports. As is, with the air moving in opposite directions where they meet, significant turbulence will result. This could result in noise from the port and other problems related to port tuning.

[mikee12345]

When i saw the 'blah blah' i thought skinnyboy would be involved

The unpowered speaker will act like a PR if its undriven wont it?

[BillFitzmaurice]

Yes, the undriven driver would act as a PR, but not a very good one. Since only one driver would be energized the total driver Vas would be halved, which means the cabinet would be double the size that it should be, while the second cone acting as a PR would drop the box frequency by perhaps another octave. The Fb would be so far below spec that the remaining speaker would not work well at all.

For the size box you're ending up with in this scenario I wouldn't do it, unless they are stereo woofers operating into the midrange. Using two boxes will give only an additional 6dB output, and you can get a lot more than that from the same size box by going with a horn loaded design instead, assuming this is a sub and that the drivers are at least 10s.

[mikee12345]

Bill F,have you ever consided growing a FAQ page for people who ask questions like this?

Ive considered starting a basshorn walkthrough which others could add to.

Its always a considerable task,but perhaps it will save some effort.

[SkinnyBoy]

thanx for the input guys, it was for in a car, but I think I'll go with sealed anyway....

[Volenti]

I've made a few enclosures along those lines before, including one with the drivers facing each other (like in a tripple chamber bandpass)

They work quite well, very little port noise.

[BillFitzmaurice]

Bill F,have you ever consided growing a FAQ page for people who ask questions like this?

I don't think it would be worth the effort. The Audio Asylum has a FAQ section, and I'd guestimate that at least 25% of the newbie posts there could be answered by simply using it. However, that takes time, and the average poster finds it easier to just ask his question in the open forum rather than devote ten minutes to research.