To improve the performance of an old vibratory feeder, be it a vibratory bowl feeder or a linear vibrator, one needs to check and set the gap between the coil and magnet. The air gap between the coil assembly and armature plate or magnet is very important. If the air gap is too small, the coil will clatter and make a lot of noise; if it is too large, the energy will not be used efficiently, causing the coil to overheat and even burn or fail. The air gap must be checked and maintained as given in the operating or maintenance manual of the manufacturer. If the air gap needs to be reset, adjust it so the pole faces are as close as possible without striking. This will generate maximum power with minimum amperage or current draw.