Tracker Action:

When the key is depressed by the organist, the tracker linkage pulls the pallet valve open. Pressurized air inside of the pallet box escapes past the pallet valve and fills the channel of air under the pipes of the note played. Air passes out of the channel, through toe holes, into the feet of the pipes, causing them to sound.

Electro-pneumatic Action:

When the key is depressed by the organist, the windchest magnet is activated. The magnet in turn exhausts the primary pneumatic, activating its valve. The primary pneumatic valve exhausts the secondary pneumatic whose valve leads directly into the channel under the pipes. The valve drops down and air escapes past the secondary pneumatic valve and fills the channel. Air passes out of the channel, through toe holes, into the feet