okay so this is simply another try at making boxes smaller with compromises.  I don't really care for any compromises, and I like to try to keep the air volumes and use folding, and other things to make a box fit where I want it to.  (thank god for fiberglass and sand! ((sand is useful sometimes in figguring the true volumes of boxes molded to the inside of trunks, kicks, hatchbacks, and spare tire things.))

You say that it's not aperiodic loading, but the carpet is the restrictive membrane. Isn't the restrictive membrane and aperiodic membrane making it aperiodic loading??

This is my last post on this thread, I promise.

This is from Steve:

"It can also be used without the lid by flipping it over on a 1/2 pile carpet with pad.  The floor becomes the lid at that point and seals up the box.  The Q-Loss through the carpeting creates an action similar to a varo-vent allowing the box to breath.  Direct coupling to the floor through carpet raises the efficiency, lowers the cut off frequency, and offers the richest sound."

Notice he says it "creates an action similar to a varo-vent" through reducing the cabinet Q. He does not state that it becomes an aperiodic design, which would require a restrictive vent/membrane to accomplish. He is referring to the fact that the cabinet on the carpet is not a perfect hard seal and there is some loss of containment of the pressures generated and the cool part of it is that those losses stimulate the floor, directly. ...... making it behave like an aperiodic loading? Who knows?

Now .....  don't make me reach back there!

The only reason J_ROCK is still hanging with you here is to demonstrate to 60 that I really should be argued with ..... which is true.

Really ..... that's all I'm going to say.

Ok, now there is one thing I still don't understand.

I understand HOW it works, now.

Why is it not aperiodic?

Aperiodic enclosures are very small boxes that "breathe" through a moving membrane.  Both the membrane and cone can not be in the same exterior space.  Either the membrane part has to be isolated by cutting a hole in the car so that it is outside, or the subwoofer has to be isolated from the rest of the trunk in a similar fashion to free air woofers.  The "box" has to be as small as possible (ideally the membrane should be right up against the sub), since it is used only for coupling the sub and membrane.  Aperiodic membrane configurations are very hard to design and tune, but give good frequency response and respond faster to transients, giving accurate and tight bass as opposed to boomy sound.  They are not ruled by Thiele-Small parameters like other designs, so any woofer would work with the membrane.

Mainly those two things, the carpet will nto move, and the membrane and woofer are not isolated.

okay I get it now, but I can't say "I get it" until I have figgured out every aspect of something... probably something really annoying o you guys, but I don't do it on purpose really.

I like learning.