Originally Posted by chimchimm5

It'll work but will sound terrible unless you compensate with enough power.

My friend and I used to build calculated enclosures for speakers and sometimes prototyped the design with cardboard... (to get a feel for size/design, not for sound)

The enclosure is necessary to act as a baffle which affects the low frequencies more than the highs. First, the enclosure separates the front of the driver from the rear, which prevents the larger wavelengths from cancelling each other out. The volume of the enclosure creates a resistance to the various frequencies which affects the frequency response; ie the Q value.

My guess is that the flexible cardboard will act as a larger effective baffle than the actual volume of air. This will cause the bass response to fall off. Blah blah blah....

Bottom line... the cardboard box will "work"... sorta. But as far as speaker boxes go, it's "bad". Then again, the average person putting together a random, uncalculated wooden/plexi/fiberglass box isn't much better.

This can all be compensated for with strong amps and a properly set equalizer.

Originally Posted by wombatsauce

Well said. Whatever floats one's boat, but I do not think I would have done that. I have built lots of speaker boxes years ago, many based on "The Loudspeaker Cookbook" but never thought to build one of flexible material except as a joke to make the most annoying device ever (old crappy 10" sub + Home Depot sheet metal "box" riveted together with 1m by 1m sides for extra flap + bass test CD to "wake up" my brother fun fun fun fun).