In the related art, a Karaoke device displays lyrics and model pitch on a display (for example, see Patent Literature 1). The pitch is represented as a so-called piano roll. In the piano roll, linear images depending on a sound start timing and a sound length of each note are displayed, on a screen in which a vertical axis corresponds to a scale (in a state where the keys of the piano are arranged vertically) and a horizontal axis corresponds to a time. This allows a singer to visually recognize the timing to sing and the pitch.