Mechanics in plain English • Instruments & Equipment
How an accordion makes sound
Air from the bellows sets free reeds vibrating. The interesting part is how the player controls that air, the reed banks and the colour of the voice.
An accordion is an air-driven free-reed instrument. The player opens and closes the bellows, valves route air through reed plates, and the keyboard or buttons choose which paths speak. The visible gesture is large, but the sound depends on small tolerances, responsive valves and the relationship between the instrument’s voicing and the player’s pressure.
Registers change the combination of reed banks that sound. That is why two instruments with similar outer dimensions can have different colour, weight and response. It is also why a recording is not a complete specification: microphone distance, room and player technique shape what you hear.
For care, the mechanism explains the boundary between daily handling and specialist work. Keep the instrument supported, dry and clean. Do not treat a sticky key, air leak or tuning problem as an invitation to open the reed blocks without the right tools.
Source note: Museum and instrument collection references. Accessed August 24, 2026.