The character and arrangement of the piece, written in 1911 for piano solo, seem predestined for this arrangement: Bartók's “barbaric” Allegro, a work of high technical standard and complex harmony, was arranged by Martin Opršál for four hands – however, these do not move over a piano keyboard, but use mallets with which they scurry over five octaves of a marimba.

Bartók's idea, which in this piece already gave the piano a percussion-like character through a driving pulse in fast tempo and ac...