No. 2 in C minor, BWV 847

Prelude

This prelude is rather challenging both technically and musically. In pieces like this prelude, where arpeggiated chords are present, playing them as solid chords rather than arpeggios can help in understanding their structure. For example, in measure 1, assuming D is a non-harmonic tone, this measure is composed of C, E-flat, and G. Measure 2 is C, F, A-flat; measure 3 is B, D, F, A-flat; and measure 4 is again C, E-flat, G. Expressed in chord symbols, this would be I, IV, vii°7, I. From this, the dynamics for these four measures can be determined. Specifically, since the tonic chord in measure 4 is the resolution of the diminished seventh in measure 3, it should be played softly. Then, consider which of measures 2 and 3 has higher tension to determine the dynamics for these four measures.

A sequence follows, with notes descending by a second in each measure. From around measure 21, the notes gradually ascend, reaching the presto at measure 28. This is followed by a cadence. Regarding this descent, for example, the melodic note E-flat in measure 5 descends to D in measure 6. The melodic note D in measure 7 descends to C in measure 8. While gradually descending through such two-measure sequences, ensure that the melodic note in the latter measure of each two-measure unit does not become louder than the melodic note in the preceding measure; if possible, it should become softer. Maintain the order within these two-measure units while gradually diminishing to reach measure 21.

Another point to note is the cadenza in measure 34. This is written precisely in 4/4 time. There is not a single superfluous rhythm. Performers should firmly grasp beats 2 and 4, initially playing exactly according to the note values. Once accustomed, they can play more improvisationally, avoiding a metronomic feel, but always remember that this is based on a prior understanding of the written rhythms and note values.

Regarding musical interpretation, although it is in C minor, it should not be played with a dark atmosphere. Rather, it can be performed actively and optimistically.

Fugue

This fugue is precisely ideal for beginners. Students who have completed the Sinfonias and are moving on to the Well-Tempered Clavier will find it easier to start with this fugue.

There are mainly two types of articulation to consider. Please look at the beginning of measure 1. The two sixteenth notes on the upbeat of beat 1 should be legato, and the two eighth notes on beat 2 should be staccato. Next, an option arises on beat 3. The pattern of an eighth note plus two sixteenth notes written on beat 3 appears frequently thereafter. There is an articulation where this eighth note is connected legato to the sixteenth notes, and another where the eighth note is played staccato. Either choice is acceptable, but once decided, consistently adhering to that articulation throughout will clarify the presence of the musical material. From a technical standpoint, it will be easier later on if the eighth note is also played staccato.

Now, since it is a three-voice fugue, each voice must be independent. Since the three voices are written as distinct parts, the performance must not be a jumbled mess lacking order. Therefore, articulation must be strictly observed in all situations. For example, look at measure 8. From beats 1-2, the sixteenth notes appear in the left hand, which can be easily played legato, with the second beat staccato. However, from beats 3-4, there are sixteenth notes in the alto voice that one would want to play legato, but the soprano simultaneously enters with staccato. On beat 3, the soprano must be staccato, and the alto must play the sixteenth notes legato. The trick is to practice this section extremely slowly. First, play C and F on the upbeat of beat 3 simultaneously, then sustain the F while cutting the C short. Try practicing cutting the C short and staccato while holding down the F.

For teachers, when instructing this fugue as a typical fugue, it might be helpful to use the analogy of a choir. If a three-voice piece is considered a three-part choir, and assuming the volume increases as more voices enter (because more people are singing), then at measure 7, where all three voices first come together, it is appropriate to instruct students to play dynamically louder. Therefore, measures 1 and 2 should begin quietly, like the high register of a pipe organ. In measure 3, with the addition of a second voice, the volume should increase slightly, and by measure 7, a forte dynamic would be appropriate.

After all three voices join, through two sequences in measures 9-10, the piece modulates to E-flat major in measure 11. In the E-flat major section, a softer and lighter color than C minor would be appropriate. Subsequently, through another two sequences in measures 13-14, it modulates to G minor in measure 15. While the tone quality should change with each key, G minor can be played with a relatively high-tension, sharp sound. Please strictly observe the articulation in measure 16 as well.

After reaching measure 20, C minor continues until the end. In the coda from measures 29-31, there is an octave C in the left hand. Imagine this as the sound of the thickest pipes on a pipe organ.