Posted by Wayne Parham [ 67.66.230.68 ] on April 16, 2005 at 11:27:17:

In Reply to: Re: In over my head! Fostex 206 cabinet posted by GM on April 15, 2005 at 11:00:02:

Not only is the length important but the positions of the driver and the opening in the cabinet. Depending on where those are, the standing waves can reinforce or cancel, and if the Helmholtz frequency is in the passband, it will have an affect as well. So I think your characterization of the two kinds of systems "morphing" is a good one, but I don't think it is accurate to characterize a tall vented box as being necessarily a transmission line. If the standing wave phenomonenon plays a large part in overall system response, then I think labeling it a transmission line makes sense. But if the Helmholtz frequency plays more of a roll, then it is a bass-reflex cabinet. And if they both do, which is entirely possible, then the system is a hybrid, having "morphed" as you say between the two.

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