I received my Aura Pro Bass Shakers yesterday. I had to track them down, as FedEx was holding them hostage. It's such a pain when vendors require signature for delivery. But I got them, and got them installed last night. Woohoo!
The first question was, where do I mount them? Ideally, it should be in a place close to the center of the chair (center from back to foot rest) and near lots of frame supports to make the vibrations radiate to as much of the chair as possible.
Next problem. How do I mount a 4" square device onto a 1 3/4" strip of wood? Two of the Bass Shaker mount points could be screwed directly into pilot holes I drilled into the wood. The other half of the transducer would have to be braced. I opted for the steel slotted angle bar
you'd typically find in a garage holding up a garage door opener, available at pretty much any hardware / home improvement store. The angle makes the bar rigid. I got a 5' strip of it and used a grinder to cut it into 6" pieces. A lock washer, nut and machine screw secure the shaker to one end of the bar; and a flat washer and drywall screw join the bar with the chair.
Incidentally, the screws I use are magic. You buy them by the plastic bucket at Wal-Mart. They're black -- I think they're labeled as drywall screws -- and 1 3/4" long. I use them for everything. I use them to hang pictures and mirrors, and used them instead of the crappy little flimsy screws that came with my window blinds. One time in college, I screwed one into a cinder block with a manual screwdriver just to see whether I could. It's nearly impossible to strip the heads of them, and they will hold your entire life together.
In retrospect, if I'd realized I would be mounting the slotted angle bars at angles, I would have just used 6" steel repair bars instead and saved myself the trouble of grinding. You find them wherever you find angle braces, chair braces, and the like; also at pretty much any hardware / home improvement store. Hindsight = 20/20.
Eh well, they're installed nonetheless, they're stable, and they don't interfere with reclining. I got them wired up and tested them. They provide ample kick, wired for a 4 ohm load on a 100w mono sub amp crossed over at about 70Hz with the gain at about 6/10. My wife and I watched the opening sequence for Quantum of Solace to break them in a little, and watched a few minutes of a comedy to make sure they aren't going to rumble inappropriately. The wife approves.