Here is a record to startle and delight those listeners who enjoy breaking free of ties previously considered sacred. For Misha Alperin and Mikhail Rudy, the music of Bach, Mozart, Schumann and Debussy et al can represent a starting rather than a finishing point, and their improvisations are a teasing and sophisticated mix of the urbane and elegiac. Inspired by the experimental jazz pianist Lenny Tristano, they extend Schumann’s Vogel als Prophet into a requiem, for Rudy ‘like a journey through a forest of crystal’. And if Schumann’s original brevity is the soul of wit, this elaboration is both a serious and intriguing response to his inimitable and seemingly complete poetry.

Elsewhere, Debussy’s Etude pour les huit doigts is embellished with flashing asides while Chopin’s wistfulness in his early A minor Mazurka is transformed into a hypnotic funereal tread. Prokofiev is subjected to high-jinks that would surely have won even his hard-won approval, while Scriabin’s exotic and far-reaching idiom is combined with free-wheeling jazz elements. The sexy ache of Alperin’s Prelude from his Prelude and Vivace is hard to resist and so, like two adults determined to disobey a ‘keep-off-the-grass’ sign these two intrepid explorers ‘enter harbour’s scene for the first time’. Above all, this disc is an act of warmth and sincerity rather than mere cleverness or presumption. The recordings are excellent and the notes include moving essays by both pianists.