These soundpads are $19 peel and stick drivers. Reportedly the 12 inch by 18 inch (rough dimensions) flat shipping boxes work about the best and sound better than you'd ever imagine.
I bought a pair of those last year. Stuck them on all sorts of things:
Carboard boxes, foamcore, matteboard, Plexiglas, glass, wood, Masonite - they universally sounded awful. And put out very little sound, which at least was a good thing.
NXT has a ways to go, if the Soundpads are any indication.
