Pallet

Pallet
Pallet

The valve which shuts off air that would otherwise reach a pipe. The pallet is usually located underneath the top-board or on one side of the chest carcass, and connected via a boring to the toe-hole that feeds the pipe with air.

When the relay sends an electrical signal to the chest magnet to play the note, the action in the windchest opens the pallet and wind from inside the chest reaches the pipe and the note sounds.