a musical instrument having a housing . a well is formed in one surface of the housing and adapted to receive a card . a slide is mounted on the housing for movement across the surface of the card . the card containing printed indicia , each of which represents a note of a musical composition with the indicia arranged in a generally rectangular matrix . the indicia on the card are arranged in one direction across the matrix to indicate the sequence of notes played in a musical composition from the beginning to the end thereof . the indicia are arranged in the direction across the matrix extending at right angles to the sequence of playing to indicate changes in frequency of the notes from the lowest frequency on one side of the matrix to the highest frequency on the other side . the slide extends across the card and the well in the direction of the sequence of playing the notes of the composition . the slide is mounted to permit its movement across the face of the card in the direction of change of frequency and the slide can be stopped at any selected position in this direction . an electrical contact is carried by the slide . a plurality of stationary electrical contacts are positioned in the path of movement of the slide contact . the card is indexed so that all of the indicia representing a note of particular frequency aligned with a particular stationary electrical contact so that positioning of the slide over the printed indicia of notes of the same frequency on the card will position the slide contact and a particular stationary frequency contact in electrical engagement . an electronic apparatus is connected to each stationary frequency contact to sound a musical note of a selected frequency when the slide is positioned over the printed indicia on the card representing the notes of that frequency .