Bus Bar

In most Hammond organs there are nine busbars that run the length of each manual under the keyboard. Each key pressed causes nine contacts to connect, one contact to each busbar. These nine contacts are wired to the ToneWheels that make up the harmonics for that key. Thus each busbar mixes the tones for each harmonic. The busbars are primarily steel with a palladium wire spot welded across the length of the bar. Each key contact has tiny piece of palladium which contacts the busbar wire when the key pressed. The busbars are adjustable to correct for wear caused by repeated key closures in the same spot. However, this adjustment should generally be left to a skilled technician. Your manuals may need a ?Bus Bar Lube Job if the notes are scratchy, intermittent, and don't respond to the busbar shifting procedure (see HowToCleanKeyContacts). Again, this procedure is probably best left to a professional technician because you can easily damage something by forcing things.