 Like ... Chopin  , write pianist and academic Kenneth Hamilton , " Alkan 's musical output was centred almost exclusively on the piano " . Some of his music require extreme technical virtuosity , clearly reflecting his own abilities , often calling for great velocity , enormous leaps at speed , long stretches of fast repeated notes , and the maintenance of widely spaced contrapuntal lines . The illustration ( right ) from the Grande sonate is analysed by Smith as " six parts in invertible counterpoint , plus two extra voices and three doublings – eleven parts in all . " Some typical musical devices , such as a sudden explosive final chord following a quiet passage , was established at an early stage in Alkan 's compositions . Macdonald suggest that