are musical instruments
that produce sounds
from a reed vibrating
in a chamber, as opposed to "fixed reed" instruments, which use a vibrating reed "fixed" to (or vibrating against) some other part of the instrument.
The oldest known free-reed is the Chinese sheng, widely accepted as the musical ancestor of the harmonica and accordion.
Other well-known free-reeds include the bagpipes, bandoneon, melodica, and reed organ.