Multiple ports?

[theCybe]

Two scenarios, progressively less original :)

By the way:

The following words are either very common, too long, or too short and were not included in your search: different ports

1) Is there an advantage to using multiple ports in a single chamber to achieve a desired 'tune'? Is this somehow mathmatically preposterous?

2) In a box with multiple subs, multiple chambers; Is it rediculous to have each chamber tuned an increment higher than the next?

My thought process suggests this would help fill out whichever area lacks;

In other words, the range lost in a 20Hz tune would be covered by a seperate chamber tuned at 30, 40, etc.

I'm aware of the bottoming out concept, whereas there is insufficient resistance in a, say, 60hz tune for a 30Hz note; Aside from that, seem reasonable? Are there some cancellation issues I've missed?

3) Passive radiators; ? A cone assembly without a driver; Understood; but the application / benefits / math involved to use that?

4) Membrane; A clothed port; What does this entail / achieve?



Can't wait to see these replies =)

[jellyfish420]

3) Passive radiators; ? A cone assembly without a driver; Understood; but the application / benefits / math involved to use that?


a cone is a driver. its a basket, and cone with no motor(magnet)

[hoss]

passive radiators act as a sort of port. they work in the same manner, just that one is more obvious than the other. a PR vibrates just like a sub, they are tuned to a certain freq/application, and they roll off the low end just like a port(24Db/octave).

a membrane would consist of something like a verio-vent. a covered port, or some other means of porting intended to slow down air oscillations in order to help control impedence rise. sort of like trying to confuse the woofer into thinking that it is in a sealed enclosure.

your question about different tunnings in a box, sounds like a bandpass box :)

having identical woofers in different boxes with different tuning might yield some odd results. more than likely, interference and cancellation.

hope that helps some :)

[theCybe]

I killed the cat.