Harmonica, preferably a diatonic harmonica, comprising at least: a. a comb comprising a plurality of chambers each comprising an opening configured to allow the user's breath to pass through, each chamber defining an oscillatory space for a blow reed and an oscillatory space for a draw reed, the blow reed and the draw reed of each chamber defining a pair of complementary reeds; b. a first plate comprising a plurality of blow reeds, the first plate being arranged opposite a first face, preferably an upper face, of the comb, each blow reed of the plurality of blow reeds being configured to oscillate in its oscillatory space when the user blows at least into the chamber defining said oscillatory space; c. a second plate comprising a plurality of draw reeds, the second plate being arranged opposite a second face, preferably a lower face, of the comb, each draw reed of the plurality of draw reeds being configured to oscillate in its oscillatory space when the user draws in breath at least from the chamber defining said oscillatory space; the harmonica being characterised in that: d. at least a portion of the chambers of the plurality of chambers comprises at least one material projection, each material projection being arranged at least partly opposite a portion of a draw reed and being configured to reduce the oscillatory space of the draw reed and to enable the oscillation of the blow reed of the complementary pair of said draw reed when the user draws in breath from the chamber of said draw reed, preferably by positioning their tongue so as to cause the blow reed to oscillate; and/or e. in that it comprises at least one additional plate arranged opposite a face of the first plate, preferably opposite a face of the first plate opposite the face of the first plate opposite the first face of the comb, and comprising at least a plurality of additional material projections, each additional material projection being arranged at least partly opposite a portion of a blow reed and being configured to reduce the oscillatory space of said blow reed and to enable the oscillation of the draw reed of the complementary pair of said blow reed when the user blows into the chamber of said blow reed, preferably by positioning their tongue so as to oscillate the draw reed. a. a comb comprising a plurality of chambers each comprising an opening configured to allow the user's breath to pass through, each chamber defining an oscillatory space for a blow reed and an oscillatory space for a draw reed, the blow reed and the draw reed of each chamber defining a pair of complementary reeds; b. a first plate comprising a plurality of blow reeds, the first plate being arranged opposite a first face, preferably an upper face, of the comb, each blow reed of the plurality of blow reeds being configured to oscillate in its oscillatory space when the user blows at least into the chamber defining said oscillatory space; c. a second plate comprising a plurality of draw reeds, the second plate being arranged opposite a second face, preferably a lower face, of the comb, each draw reed of the plurality of draw reeds being configured to oscillate in its oscillatory space when the user draws in breath at least from the chamber defining said oscillatory space; d. at least a portion of the chambers of the plurality of chambers comprises at least one material projection, each material projection being arranged at least partly opposite a portion of a draw reed and being configured to reduce the oscillatory space of the draw reed and to enable the oscillation of the blow reed of the complementary pair of said draw reed when the user draws in breath from the chamber of said draw reed, preferably by positioning their tongue so as to cause the blow reed to oscillate; and/or e. in that it comprises at least one additional plate arranged opposite a face of the first plate, preferably opposite a face of the first plate opposite the face of the first plate opposite the first face of the comb, and comprising at least a plurality of additional material projections, each additional material projection being arranged at least partly opposite a portion of a blow reed and being configured to reduce the oscillatory space of said blow reed and to enable the oscillation of the draw reed of the complementary pair of said blow reed when the user blows into the chamber of said blow reed, preferably by positioning their tongue so as to oscillate the draw reed.