Fugue no. 23 en Si Majeur, BWV.892

Prelude and Fugue in B major, BWV 892, is the 23rd pair of prelude and fugue from Book II of The Well-Tempered Clavier by J. S. Bach, compiled between 1739 and 1744.

While Bach concluded the first volume with a Prelude and fugue in B minor (BWV 869), in compiling the second volume twenty years later, he placed a brief fugue in the style of a fughetta in the 24th and final position. Therefore, in the major key, for the 23rd diptych in B, he reserved a double fugue of even greater scope (104 measures, compared to 76 in the first book and nearly equal to the preceding one in B♭ minor).

The prelude that introduces it—comparable to the D minor and F♯ major preludes—is structured as a brilliant and joyful toccata. The fugue, in stile antico, is based on a dignified subject presented across four voices from low to high. Bach achieves a work of great majesty.