The prelude, marked Largo, employs the dotted rhythms of the French overture, though of course without the fugal section typically folded into that format. This constitutes a stately introduction to one of the Well-Tempered Clavier's most majestic fugues, despite its brevity. Technically a fugue with canon sine pauses (simultaneous counterpoint), it's in four voices, entering tenor-alto-soprano-bass. The principal subject takes off from a series of short pronouncements more typical of Bach's organ writing, and a significant countersubject also makes itself strongly felt, all culminating in a grand final passage.