Abstract: A graduated leverage piano action is incorporated into a piano having graduated mass hammers for striking graduated mass strings. The mass of the hammers and strings is highest for the lowest bass strings and lowest for the highest treble strings. In the piano a plurality of keys are supported by and pivoted about a balance rail which divides each key into first and second lever arms. The length of the second lever arm is defined by the location of a capstan screw which is coupled to each key. The length of the second lever arm decreases as the mass of the hammers increases. A complex mechanical linkage is coupled to each hammer and is positioned above each capstan screw for displacing each hammer when contacted by an opposing capstan screw contacts the third lever arm. The third lever arm is displaceable by the corresponding capstan screw.