Home / Forums / General melodica discussion / Flexible Ergonomic Melodica Mouthpiece? / Reply To: Flexible Ergonomic Melodica Mouthpiece? Reply To: Flexible Ergonomic Melodica Mouthpiece? December 20, 2015 at 12:54 am #6589 Alan BrintonParticipant What the heck, I’ll go for it. One of the issues is that there’s quite a bit of variation in the diameters of melodica mouthpiece openings. Since I have a large collection of melodicas, I can check it out in relation to different sizes.