In this paper, we describe a computer-based solo musical instrument for live performance. We have adapted a Wacom graphic tablet equipped with a stylus transducer and a game joystick to use them as a solo expressive instrument. We have used a formant-synthesis model that can produce a vowel-like singing voice. This instrument allows multidimensional expressive fundamental frequency control and vowel articulation. The fundamental frequency angular control used here allows different mapping adjustments that correspond to different melodic styles.