Cut the outer membrane away from the speaker, except for the area where the wires are attached. Leave a 1-inch piece of the upper membrane intact where the wires are attached. Leave the entire inner membrane intact.
Mount a weight into the VC former — the cylinder in the center of the speaker. The weight can be any heavy object that will fit in the space allowed such as a stone or large metal nut. Be careful not to deform the VC former when you install the weight.
Solder the wires attached to the exterior membrane of the speaker to your speaker extension wires. Turn the chair on its side so you can work on the underside of the seat.
Position the speaker with the gasket against the chair bottom. Slip the speaker's outer case around the speaker base and tape it to the bottom of the chair, using the duct tape.
Screw the speaker frame to the bottom of the chair, using the power screwdriver. Place one screw in each corner of the speaker frame. Ensure the speaker remains vertical, with the coil parallel to the chair bottom.
Connect the speaker extension wires to the amplifier. Connect the amplifier to your TV, PC or video game console's audio input. When sound plays through the amplifier, the speaker under your chair will vibrate. Your motion chair is now ready for more interactive gaming and viewing.