Harpsichord Strings are the sound source. Pressing a key causes a quill to pluck the string. To change volume or sound quality, pedals or levers allow the player to link each key to one or more strings, tuned to the same note or the same note in different octaves. Clavichord Strings are the sound source. The string vibrates only as long as the tangent is in contact with it.
Strings are once again the sound source.
Pressing a key causes a felt hammer to hit the string. The more force you use on the key, the louder the sound. Pipe organ Vibrating columns of air inside the pipes are the sound source. The calliope is a high-pressure, portable version of the pipe organ, originally powered by steam. Celesta Metal bars are the sound source.