Two-Part Invention in E-flat Major
A two-part invention is a piece in two voices (left-hand, right-hand), that typically imitate one another. In other words, one hand plays a short melody called a motive, then the other hand imitates it by playing the same motive, usually an octave higher or lower. J.S. Bach wrote 15 two-part inventions (and 15 three-part inventions) for the purpose of teaching keyboard and compositional techniques.
Prelude and Fugue in F-sharp Minor
The prelude here is a chorale prelude, based on the chorale Erhalt’ uns, Herr, bei deinem Wort (Preserve Us, Lord, by Thy Word).
A chorale is a German congregational hymn, on which numerous compositions from the Baroque era (ca. 1600-1750) are based. When a pre-existing melody is used for a composition (such as a chorale), it is called a cantus firmus, (“fixed song”). This three-voice chorale prelude is typical in that the cantus firmus is in the bass. For each phrase of the chorale, the upper two voices enter using the opening of each phrase in imitation, before the bass enters with the melody. This technique is called vorimitation (“imitation before”).When the cantus firmus enters, it is in augmentation (note values are made longer).
A fugue has two or more voices that imitate one another; this fugue has three-voices. The main theme, or subject, is presented by each voice (called the exposition), after which, it is developed throughout the remainder of the fugue.
Prelude and Double Fugue in A Minor
This two-voice prelude also uses a chorale, Vater Unser im Himmelreich (Our Father, Who Art in Heaven), in the bass. The right hand plays free counterpoint above the cantus firmus.
There are different types of double fugues. This fugue, in four-voices, has two subjects, hence the designation double fugue. The second subject enters one measure later than the first. Each voice takes turns playing one of the two subjects
Fugue a4 in F Major
Sonatina in C Major
Sonatina in C Major, a three-movement work, is in the spirit of the 18th-century classical sonatinas by Clementi and Kuhlau. I wrote the first two movements as an example of what I was expecting from my second-year music theory students.
The first movement (Allegro) demonstrates what is called a rounded continuous binary form. Binary means it is in two parts; rounded is an indication that the first theme of the movement returns later in the movement. Continuous means that the first part of the binary form changes keys, and does not return to the original key until the return of the opening theme.
II. Andante cantabile
Andante cantabile means it should be played at a relatively slow tempo and in a singing manner. This movement also is in rounded binary form, but part one does not change keys.
I wrote the last movement way back in 1978 as an answer to Frank Mill’s international hit of the 70s Music Box Dancer. This movement is an arch form (ABCDCBA), which is not a typical classical form. The movement works as a third movement, however, since it employs other typical classical elements, such as an Alberti bass accompaniment pattern.