Form
As you can guess from the title, this work is divided between a prelude and a fugue. A prelude is a short piece of music that may stand on its own or introduce another work; it can be thought of as a preface. This style of work first emerged during the Renaissance for lute and were known for being improvisatory in nature. This style became prevalent in musical works for keyboard and organ during the Baroque era and were combined with the fugues in the latter part of the Baroque era to create a richer tapestry of sound. J.S. Bach had a significant influence on this genre through his collection of preludes and fugues entitled The Well-Tempered Clavier. This prelude is written in binary form, which is a compositional style where the work is divided between two related sections that are repeated. The first section of the prelude (the A section) goes from measure 1 to measure 24 before repeating. The second section of the prelude (the B section) begins at measure 25 and goes to measure 51, where the coda section lasts from measure 51 to the 1st ending before repeating. The repeats go back to measure 25 and goes back through the coda section and ends with a fermata at measure 58 (end of the 2nd ending). After the release of the fermata, the piece goes into the fugue.
A fugue is a contrapuntal composition in two or more voices, built on a subject (theme) that is introduced at the beginning through imitation and recurs frequently in the course of the composition. Fugues first appeared as a way to describe any type of imitative counterpoint, but through the work of Baroque composers, they became a central concept in musical composition and appeared in a wide array of forms. This fugue begins with the subject being introduced in the oboes and clarinets at measure 59. The next group of voices (English horn, alto saxes, and cornets) enter in measure 63 with the tonal answer, which is a variation on the original theme presented a few bars earlier. At measure 64, the oboes and clarinets introduce the counter-subject leading into measure 70. At measure 70, those previous playing the the tonal answer and counter-subject enter with the counter-subject with the additions of flutes. A new voice (The alto clarinet, tenor sax, horns, and 1st & 2nd trombones) enter with the subject at measure 70 before taking over the counter-subject in measure 74. The tonal answer appears at measure 73 in the final group of voices (bassoons, bass clarinet, baritone sax, 3rd trombone, euphonium, tuba, and timpani). This four-voice texture is presented throughout the rest of the fugue with additional statements and stretto statements of the subject, tonal answer, and counter-subject. The fugue concludes with a coda from measure 108 to the end.