A published collection of musical pieces of the same genre often expresses a unity, or even a clue to unlocking deeper meanings embedded in that music. It can add an important detail to what is known about a composer's technique at a given point in time, or even allow a patient performer or scholar to discover some common thread or hidden idea that links the works.

By presenting a program of Johann Sebastian Bach’s six organ sonatas, which were published as a collection at the end of the 1720s, organist Paul Jacobs helps us search for easily overlooked nuances within these carefully composed contrapuntal explorations. Perhaps the collection arose out of pure convenience, since more than two-thirds of the 18 movements had already existed in another version before being adapted into organ sonatas. Then again, if the resulting juxtaposition is governed by a higher strategy or something entirely subliminal, hearing them played in one sitting will certainly help pinpoint anything that should be found.

The outer movements of the first organ sonata in E-flat major, BWV 525, allow the pedals to share in statements of the opening melodic subject as a fugue would do. The opening consists of a catchy motive of two simple broken triads at the beginning in the left hand, answered later by both the right hand and then the pedals. This familiar first movement also existed as both a separate organ work and an arrangement (transcribed into C major) for small ensemble.

Although the middle adagio movement in 12/8 was newly written for publication with the other sonatas, its stately arioso-like theme has since been arranged for other various ensembles. A lively pedal-point theme (i.e., every other note in a group of eighth notes acting as a drone) first ascending and then later in inversion descending, closes the sonata, while a circle-of-fifths development provides some unexpected harmonic twists.

The second sonata in C minor, BWV 526, sharply contrasts quick duple meter of the outer movements (Vivace and Allegro) with the second movement's Largo in 3/4, which forms a particularly recognizable theme out of a series of descending melodic anticipations. The final movement commences with the simplest possible melodic fragment, that is, two whole notes (playing sol to do), while the contrasting section makes ample use of a descending broken chord that lands on the leading tone to the beat that follows.

The opening movement to the third sonata in D minor, BWV 527, distinguishes itself as a slower first movement (Andante) which uses an eight-bar theme with a contrasting syncopated idea between the two hands. The second “Adagio e dolce” movement in 6/8 uses two-part harmony and a chromatic chordal descent, along with a highly melismatic interchange during the middle section. The sonata ends with a busy, scherzo-like movement with examples of furious running triplets clashing with other passages of duple meter.

An arrangement of the Adagio-Vivace sinfonia from the cantata Die Himmel erzählen die Ehre Gottes, BWV 76, serves as the opening movement for the fourth organ sonata in E minor, BWV 528. A melody constructed out of groups of simple rising fourths sequencing downward becomes abruptly enmeshed with a thicker texture of patterns dominated by distinct “tierce coulé” ornaments (i.e., a rapid stepwise upward movement from the lower to upper note in a third). In the final “Un poco allegro” movement, running triplets in 3/8 actually create a 9/8 feel, similar to the ending in the previous sonata, but more complex.

In the fifth organ sonata in C major, BWV 529, a lively broken arpeggio flourish makes for a joyful expository beginning, while a melancholy largo second movement proceeds with long melodies placed abundantly within a precise da capo form. In the third movement (which Bach newly composed for publication of the cycle), a rousing motive in eighth notes that opens by avoiding the downbeat makes for rich material developed ceaselessly and thickly contrapuntal.

The sixth and final organ sonata of the cycle in G major, BWV 530, represents the only piece of the set in which all three movements are original compositions not known in any preexisting instrumentation or versions. With both hands playing in unison, repeated quarter notes on the tonic firmly establish the opening motive of the Vivace first movement and make it easily recognizable throughout.

In the second movement (Lento) in 6/8, a mournful melody is subtly punctuated with chromatic harmony that starkly reveals itself in a descending scale in the highest voice at the end of a 16-bar section, which is repeated once and returns following an 8-bar interlude, in invertible counterpoint (i.e., left hand melodic line now on top played in the right hand, and vice versa). The melodic subject for the third movement artfully ends on a half cadence which allows the running 16th notes of the development that follows to flow effusively.

Gregg Wager is a composer and critic. He is author of Symbolism as a Compositional Method in the Works of Karlheinz Stockhausen. He has a PhD in musicology from the Free University Berlin and a JD from McGeorge School of Law.