Made as an electric practice drone for tabla and sitar players, the Sruthi box emits a tone along with two sympathetic tones, all three each having their own volume knobs. There is a tune knob that affects these three tones and also a toggle switch that switches between major and minor. This can be 'played' like a sign wave generator, using the tune dial to sweep to different notes. Currently there is no output other than its internal speaker. On high, it distorts really nicely. It takes a very good ear to play, like a violin or Theremin. This was given to me as payment for playing on a record. Thanks Pramod!