Playing with the idea of using a transducer setup to vibrate the floors in a scene. Saw it at Knotts a few times and it got my wheels spinning (or at least shaking anyway..) Anyone out there build these? Seen a setup over at frightprops, but would like to make it cheaper. Or larger and more intense. Well, preferably a combo of the two. Anyway, anyone out there have a diy for this?