Writing Piano Accompaniments
The Piano Accompaniment
Requiring a piano accompaniment for your choral arrangement is an important decision. While it provides a contrasting timbre and interplay with the voices, it is tuned in equal temperament. This means it is basically out of tune with the pure intonation of unaccompanied voices, in which upper harmonies are overtones of the bass notes. The possibility of having to use a piano that is not well-tuned is a potential issue. However, the interest and added dimensions that a piano can bring to the arrangement may offer compelling reasons to use it. Many modern choirs use a digital piano that is portable and always in tune.
An exact copy of the vocal parts is not an accompaniment, but many choral scores include it to help the singers learn and conceptualize the music. These piano parts will typically be marked “For Rehearsal Only” in a cappella arrangements. It is rarely a good decision to double any of the vocal parts for extended periods on the piano. It may be helpful for inexperienced singers to hear some of their pitches, but often providing a harmonic context with the piano is more effective. One common practice is to double bass notes an octave below the lowest voice part, particularly if the choir lacks deep bass voices.
The range and flexibility of a piano make it good choice for choral accompaniment. It is primarily a percussion instrument, and can provide all types of background figures, obbligato lines, and chords. Typically, patterns are employed to establish a harmonic context for the melody and introduce rhythmic activity. I like to call this motivating the harmony.
Accompanimental Strategies
- Alternate between bass notes and block chords. This common device is often used to support a single melodic line.
- Arpeggiate chord members upwards and downwards where the lowest note becomes the bass, and the figure remains constant in its shape. The Alberti bass is a simple example of this type of figure.
- Create a tremolo figure that alternates between two different pitches to provide rhythmic interest. The two pitches must be chosen carefully to elucidate the harmonic content clearly, and avoid conflict with the vocal lines.
- Combine arpeggiated and tremolo figures together to create a sequential pattern. These patterns can be adapted to the harmony of the moment and transposed with variations.
- Imitate fragments of the melodic line in the accompanimental part. This integrates the two functions and creates new expectations for the listener.
- Introduce moving inner voices using passing tones and suspensions to create harmonic interest and variety.
- Consider the counterpoint between the voices and piano. Best practices are to move one part while the other is stationary, and include contrary motion where possible. An obbligato line that complements the primary melody can be very effective.
- Begin with a sparse texture in the accompaniment in most cases, which can always be thickened as needed. A good place to start is with a strong bass line.
- Repeat block chords in a regular pulse or rhythmic pattern to heighten the forward progress to points of arrival and lend power to the overall texture.
- Quietly roll or arpeggiate long sustained chords to provide a serene background or prepare the entry of voices.
There are endless possibilities, and the best accompaniments use a combination of figures and devices to enhance the musical flow. The character of the music, the range, and density are critical factors in determining the most suitable choices. In general, it is better to understate the accompaniment than to build an overly active texture that competes with primary melodic material. That being said, sometimes an arranger will want to showcase the pianist as an equal partner with the choir.
Introductions and Endings
A piano introduction to a choral work serves several important functions. It establishes the harmonic context along with the tempo and rhythmic framework. It literally sets the tone for the piece. It could be as short as a chord or two, or a few measures with lines that feed pitches to the singers.
The introduction frequently contains a scrap of the melody, as well as an accompanimental pattern that continues as the voices enter. Some arrangers write the introduction after the body of the piece is completed, drawing on materials that they have developed. It may be effective to use the last few phrases of the melody as an introduction.
Endings often involve the repetition of the last line of text, with the accompaniment supporting the final cadence. Variation is often added to the repetition, along with a ritardando. A retard can effectively be built in by augmentation. This amounts to increasing the rhythmic value of the notes, broadening and imparting a sense of finality. It is not uncommon for the piano to drop out of the texture for the ending, leaving the last phrase to hang in the air.
The piano frequently provides an interlude between sections. This can be a welcome contrast in texture and timbre, and can effectively prepare the choir and listeners for a modulation or a tempo change. Less frequently, the piano becomes the focal point of the arrangement and the choir supports it by humming or singing mono-syllables in the background while the piano presents melodic content.
Many of the strategies mentioned here are exemplified in the piano accompaniments for choral arrangements with in the Materials below.
Materials
Choral Arrangements with Piano Accompaniment
- Example: So shy shy shy
- Example: Hello is what a mirror says
- Example: death is more than