Toccata Und Fuge F-Dur, BWV 540 - 2. Fuge (F大调托卡塔与赋格，作品540 - 第2首 赋格)-Marie Claire Alain

The toccata starts with a large linear canon (imitation theme, one hand imitating the other) over a pedal point in F major. It is then followed by a pedal solo vamping material from the canon. The canon is reiterated with some variations in the dominant in C major. This time the hands are switched, and the left hand leads the right. This is again followed by a long pedal solo. The two large canon flourishes cover 108 measures of the composition. The pedal solos cover 60 measures. The concerto movement exhibits a seven-part structure. The canons and pedal solos effect the departure from the home key of F to the dominant C, and the entire rest of the movement, with its concertante 3-part imitation and striking "proto-waltzes", constitute the harmonic return. This formal pattern is unique within Bach's ?uvre. Hermann Keller expresses his rapture as follows: " At the beginning the extensive linear construction of the two voices in canon, the proud calmness of the solos in the pedal, the piercing chord strokes, the fiery upswing of the second subject, the bold modulatory shifts, the inwardness of the three minor movements, the splendour of the end with the famous third inversion of the seventh chord, who would not be enthralled by that?" Because of the range of the pedal parts, the organ at Wei?enfels, with a pedal compass of f1, may be the organ the composition was written on. The Toccata (as a prelude) is proportionally the largest of all Bach's works in the format of prelude-fugue. It is often treated as a show piece, with the ensuing fugue omitted. The Toccata's rhythmic signature suggests a passepied or a musette, although the monumental scale of the movement does not support these characterizations.Nor does the harmonic adventurousness: 45 measures after the second pedal solo there is a dominant chord which resolves deceptively to the third-inversion dominant applied to the neapolitan. In particular, the doubled root is found to move outward in contrary chromatic motion to a major 9th; in the bass is a descending augmented unison, which absolutely could not be farther from the expected fifth. Bach implements this powerful deceptive cadence three times in the piece; it would not become idiomatic until Chopin and Tchaikovsky.