In February 1987 Keith Jarrett recorded the first book of Johann Sebastian Bach's Well-Tempered Clavier on piano, the first of his Bach recordings for ECM. On 7 March 1987, before that studio set came out, he played the complete Book I in concert at the Troy Savings Bank Music Hall in New York state. This double album, released in 2019, is the archival tape of that evening, the 24 preludes and fugues heard in one sitting before an audience.

The hall in Troy is known for its acoustics, and the concert was engineered by Tom McKenney. For the release Manfred Eicher acted as executive producer and Christoph Stickel mastered the tapes. The cover image is by Mayo Bucher, and the booklet carries photographs by Yasuhisa Yoneda. The studio version followed on ECM in 1988, so this concert stood unheard for more than thirty years.

Bach completed Book I in 1722: 24 pairs of preludes and fugues rising chromatically through every major and minor key, from C major to B minor. When Jarrett's studio album appeared, many listeners were surprised by its restraint. He spoke of "the process of thought" in Bach and said that "this music does not need my assistance", so he lets the lines carry the expression. The live set keeps that clarity, with sparing pedal, but the playing breathes more freely in front of an audience. The C major Prelude opens with a slight hold on its first note, the E-flat major Prelude has rubato and flow, and the closing B minor Fugue sounds hard-won and valedictory. The two discs last about 50 and 54 minutes.

Writing in The Observer, Fiona Maddocks noted that "he never imposes himself in these restrained, elegant performances". Jessica Duchen in BBC Music Magazine heard "poetic playing, but poetic in a wholly 18th-century sense". On MusicWeb International Dominy Clements called it a very good performance, livelier in sound than the studio set, while noting a few small slips. Few jazz musicians have gone as far into the classical repertoire, from Bach and Mozart to Shostakovich, Bartók and Barber.

Issued on ECM New Series in 2019 as a double CD, ECM New Series 2627/28.