PAMDI is an electromechanical music controller based on an expansion of the common metal music boxes. Our system enables an augmentation of the musical properties by adding different musical channels triggered and parameterized by natural gestures during the “performance”. All the channels are generated form the original melody recorded once at the start. To capture and treat the different expressive parameters both natural and intentional, our platform is composed of a metallic structure supporting sensors. The measured values are processed by an arduino system that finallysends the results by serial communication to a Max/MSP patch for signaltreatment and modification. We will explain how our embedded instrument aims to bring a certain awareness to the player of the mapping and the potential musical freedom of the very specific – and not that much automatic — instrument that is a music box. We will also address how our design tackles the different questions of mapping, ergonomics and expressiveness while choosing the controller modalities and the parameters to be sensed.