THIS design produces bell-like sounds, using the multiple harmonics of sinewaves to give the tonality expected from bells, complete with the decay of each note played. In its simple standalone form, as described here initially, it is triggered by a 4 × 4 matrix data keypad. This allows the 12 notes of an octave,
including sharps, to be generated. The remaining four keys causes the octave of the note to be changed, providing a complete four-octave range.
