A polyphonic instrument comprises a geometric system coupled with a user interface and a method for generating tone using fluid. The geometric system is arranged such that each point corresponds to a mechanism underlying a malleable surface and is sequentially based upon the 12 tone system of music. The instrument also provides a new method for generating tone by the means of using fluid, whereby a specific frequency is picked up by a separate hydrophone or fluid based transducer submerged in a sealed and removable fluid containment unit having a rotational element also contained within for each note indicated. The rotational element when arranged in a series of graduated units and/or in combination with graduated sub-containment units of fluid changing in scale for separate frequencies, will generate separate tones which may be manipulated through physical and/or analog/digital electronic means.