Murray Perahia, Georg Solti - Bartók: Sonata for Two Pianos & Percussion / Brahms: Variations on a Theme by Joseph Haydn (1988)

The Sonata for Two Pianos and Percussion is (along with the more popular Music for Strings, Percussion and Celesta) the pinnacle of Bartok's fascination with exploring the percussive timbres of the piano and the expressive capacity of percussion. The pianos of Sir Georg Solti and Murray Perahia and the percussion section (3 kettledrums, xylophone, 2 side drums (one without snares), cymbals, suspended cymbals, bass drum, triangle and tam-tam) of David Corkhill and Evelyn Glennie are pretty much equals.
The result is a propulsive, thorny, cerebral, rhythmically and harmonically intricate masterpiece, which exudes a distinct mood of mystery. Listening to it, I can't help but feel it must have been a major influence on the great Cecil Taylor and his school of violently percussive and dense avant-garde/free piano improvising. Although relatively obscure, this is as stunning as anything I've heard from Bartok's range of unique masterpieces (I think I've heard them all except for the String Quartets).
The performances are stellar all around. The quality of the sound engineering and recording should impress even the fussiest audiophiles.
The Brahms piece is very beautiful, but listening to it straight after Bartok's Sonata is a bit of an anti-climax, as it is much more timid and conventional.