The pin-barrel (1) is provided for a musical box in the form of a wristwatch. The pin-barrel is formed of a set of parallel pairs of strips (3, 3'), which are connected at one end thereof to a heel (2). Each pair of strips forms a tuning fork, wherein one of the strips (3') of the pair can be set in vibration by at least one pin of a musical module wherein the vibration propagates to the other strip (3) of the pair by a longitudinal wave.