Abstract: Enclosures for a harmonica are disclosed wherein the wall of the enclosure surrounds the harmonica, provides a mouthpiece opening and an outlet opening, and forms at least one resonance chamber. A lip groove, a bulge, a cradle and a diffuser are disclosed forming a saddle-shaped surface which is concave along a front-to-back axis and convex around the ends of the enclosure. A key benefit of this arrangement is the improved control of the sound by the player's hands. Another key benefit of this arrangement is the enhanced tone and increased loudness of the sound produced by the harmonica. Supporting members are disclosed that constrain movement of the harmonica relative to the enclosure. Single-piece and multi-piece enclosures are disclosed.