Definition
The episode (in Italian also divertimento; in French divertissement) is a section of the fugue in which the subject does not appear in full. It serves to modulate toward the key of the next entry, to give breathing space after the entries, and to develop fragments of the material. In most cases it is built on sequences derived from the head, tail or countersubject.
The main techniques
- Fragmentation: a motif of two to four notes (often the head or tail of the subject) is isolated and repeated.
- Sequence: the fragment is repeated on different scale degrees (usually descending by thirds or by seconds, or along the circle of fifths).
- Canonic imitation: two voices pass the fragment back and forth at a short distance (half a bar, one bar), often at the fourth or fifth.
- Double counterpoint: the same episode returns later with the voices exchanged.
- Inversion of the fragment.
- Pedal: one voice holds a note while the others develop the fragment.
Typical sequences
- By descending fifths: C–F–Bb… diatonic in C: C F B E A D G C (I IV vii iii vi ii V I). The most used for returning to the tonic.
- By descending steps with a chain of 7–6 or 2–3 suspensions.
- By ascending steps with 5–6 (C – Am/C… D – Bm/D…): creates growth before an important entry.
- Modulating: the sequence leaves the key (example: C → A minor → D minor → F) following the tonal plan of the fugue.
Example from the repertoire
In the Fugue in C minor BWV 847 (The Well-Tempered Clavier I), right after the last entry of the exposition, an episode modulates from the tonic to the relative major (Eb) by means of a sequence built as an accompanied canon at the fourth. The arrival is marked by a cadence and by the first middle entry, with the second countersubject adapted to the major mode.
Example of construction (C major)
Teaching subject: C5 G4 A4 B4 C5 D5 C5. Chosen fragment: the tail B4 C5 D5 C5 (rise by step and return).
- High voice: B4 C5 D5 C5 | A4 B4 C5 B4 | G4 A4 B4 A4 (descending sequence by step).
- Low voice in half notes, with ties across the barline: G3 F3 | F3 E3 | E3 D3. Each second half of a bar becomes a small suspension in the bass; the notes of the fragment form thirds, sixths and fifths with the bass, and the second note of each fragment (C5, B4, A4) is a passing fourth (perfect or augmented).
- Ending: the bass rises to E3 and then descends to A2, while the high voice goes from A4 to G#4 and back to A4: cadence in A minor (E – Am) for the entry of the subject in A minor.
Plan of the episodes in a fugue
| Episode | From | To | Material |
|---|---|---|---|
| 1 | end of exposition (C) | counter-exposition or relative minor | tail of the subject |
| 2 | A minor | F major or D minor | head of the subject, in canon |
| 3 | subdominant | dominant, pedal | countersubject in sequence |
Each episode has a different character; the last often prepares the dominant pedal.
Typical mistakes
- Sequences that are too long (more than three repetitions): they become mechanical.
- Episodes with new material unrelated to the subject: they break the unity.
- Hidden parallel fifths in sequences: a sequence that contains a mistake repeats it at every step.
- Arriving at the next entry without a cadence or preparation: the entry is not heard.
Modern application
- Production: the episode is the equivalent of a pre-chorus or a build: fragments of the hook repeated in sequence to arrive at the drop or the chorus.
- Film scores: modulating sequences on fragments of the theme are the classic way to accompany a transition scene while keeping the theme recognizable.
- Choirs: in choral episodes it is best to give the fragment to two sections in imitation and leave the others on long notes, so the text stays clear.
Related topics
Fugue: countersubject, codettas and episodes, harmonic sequences, chains of suspensions, stretto, school fugue.