The present invention relates to a method for representing musical scales by means of tiles, including pentatonic scales (arbitrary scales with five notes per octave), heptatonic scales (arbitrary scales with seven notes per octave). Major blues and Minor blues scales (specific scales with six notes per octave), and to an electronic musical device with an interface that uses this representation. More specifically, the device uses a multi-touch interface with or without strings which allows the musician to concentrate on the melodic line only, making it easier to improvise and perform music composed in one of said scales. The representation differs from the traditional interfaces on string instruments (such as a guitar) in that only the notes of a given scale (with five, six or seven notes per octave) can be played.