Mark Schimmer reported:
Recently I hooked a set of so called "Body Shakers" to my hifi rig. These are low frequency transducers (28 to 55 Hertz) which normally induce vibrations on walls or other large objects. They give a great tactile feeling, expecially on sounds like piston engines, slow firing guns, afterburner rumble and .... incoming fire (makes me almost leap out of the seat).
They are build as a stationary large coil in the casing with a moving, very heavy magnet in the center, which is held in place by two epoxy "springs". The momentum of the great mass of the moving magnet induces the vibration to the object where the thing is fastened to.
They are sold here by a German electronic warehouse, but from looking at them I would guess that it is not a German product. I also have seen them in car hifi stores (some crazies fasten these things to the floorpans of their cars here. You can hear them from half a mile, and they surely have a lot to do to keep their cars from disassembling themselves).
What I'm trying to say is that they might be sold overseas, too. They are also very cheap at 20 German Marks per unit. This is what "Body Shakers" look like:
Low frequency Transducer
My testing included fastening two of them on the underside of the table. Great. My next test will be installing them in the seat pan of my Martin Baker GQ7 ejection seat (my "office" and "simming" chair).
The body shaker is available from
HERE - Product Number: 433039-62
There are other's like those from Clark or Aura, but they are quite expensive. I think they sold the those that I have at www.meci.com for $USD 12 or 13.