Choosing Repertoire and Arranging a Song for Voices

A director sits down with a stack of songs and a fixed number of rehearsals. The job is to decide which of those songs will be sung, in what key, in what shape, and in what order they will be taught. Repertoire and arrangement are the two halves of that decision, and both of them start from the voices in the room rather than from the page.

The words carry a history. In music, an arrangement is a musical adaptation of an existing composition, and the differences from the original can include reharmonization, melodic paraphrasing, orchestration, or formal development. Arranging differs from orchestration, which is limited to assigning notes to instruments for an orchestra, concert band, or other ensemble. Arranging goes further: it adds compositional techniques such as new themes for introductions, transitions, modulations, and endings. One description of the craft calls it the art of giving an existing melody musical variety.

What a director listens for before choosing a song

The first filter is range, not taste. A song that sits comfortably for a soloist can sit badly for a section, and a section is what the director is actually writing for. The Wikipedia article on arrangement notes that the string section in a multi-sectioned orchestra is sometimes called the string choir, and the same logic of grouped, like instruments applies to voices: sopranos, altos, tenors, and basses are treated as units whose members mostly sing preconceived parts.

After range comes key. Transposition is one of the oldest moves in arranging; the article records that J. S. Bach's violin Prelude in E major was transposed down to D in both of his arranged versions, the better to accommodate the wind instruments. A director transposing a chart for a choir is doing the same arithmetic for a different set of instruments. If the key that suits the voices also suits the piano, the arrangement can stay close to the original. If not, something has to give.

How much of the original survives the trip?

Reharmonization is optional. Orchestration is where most of the visible work happens. The same passage in Mussorgsky's piano suite Pictures at an Exhibition repeats in the original, and Ravel's arrangement repeats it too, but the second time it is given a fresh orchestration with celesta replacing the woodwinds and string glissandos on the fingerboard. Nothing about the notes has changed; the colour has.

Choral arrangers work at exactly this level. A repeated verse can be handed to a different combination of voice parts, the piano part can be thinned for the second pass, and the last chorus can be opened up for the full ensemble. A director reading a chart for the first time is looking for where the arranger placed those changes, because that is what the rehearsals will be built around.

Where do range limits come from?

A score does not tell a director how many people are available on a given Tuesday. Artistic, budgetary, and logistical concerns, including the size of a hall or a pit, determine the size and instrumentation of a section, and the same constraint shapes a choir. Leonard Bernstein left the house viola players out of the 1957 Broadway run of West Side Story, partly because he disliked their playing and partly because removing them freed space in the pit for an expanded percussion section. A director with fourteen singers and eight of them altos has a comparable choice: find repertoire that uses eight altos, or find a piece where four of them can carry a line alone.

George Martin, who produced and arranged for the Beatles, warned about intonation when only two like instruments play in unison, writing that after a string quartet he did not think there was a satisfactory sound for strings until there were at least three players on each line, because two stringed instruments together create a slight beat. That caution transfers straight to a vocal section asked to sing a unison line with only two voices on it. Where a section is thin, a director has a concrete reason to divide it differently or to move the line elsewhere.

What does a head arrangement mean for a small group?

For a small jazz combo, arrangements are usually informal, minimal, and uncredited, because players work them out together rather than from a score. The Wikipedia page on musical arrangement keeps head arrangements in its jazz section, beside big band charts and named arrangers. Larger ensembles generally need notated arrangements, with a named arranger credited for them. Count Basie's early big band is the famous exception, known for head arrangements worked out by the players themselves, memorized, and never written down. Most big band arrangements, by contrast, were written down and credited to someone, as with Sammy Nestico's and Neal Hefti's work for Basie's later bands. Big band arrangements are informally called charts, and the term carried over into vocal jazz. A small Washington ensemble that learns a song by ear and commits it to memory is operating in the head arrangement tradition, even if nobody in the room uses the phrase.

For a small jazz combo, arrangements are usually informal, minimal, and uncredited, because players work them out together rather than from a score.

District Songbook, How Vocal Jazz Ensembles Work

In what order should the director teach the song?

The teaching order usually follows the difficulty, not the score. A director typically settles the notes that hold the harmony first, then the melodic line, then the inner parts that move against them, and then the sections where the arrangement departs from what the singers already know. Endings and transitions take time because they were added rather than inherited, and a group that has sung a song before will still need the new introduction or modulation walked through.

Rehearsal order across a season follows a parallel logic. Programmes are usually assembled so that the piece requiring the most rehearsal sits early in the calendar, and the pieces that are almost ready sit near the concert. No fixed rule is published for how many weeks a single arrangement deserves; a director reads it off the ensemble.

When does a director abandon a song?

When the arrangement will not fit the voices without rewriting most of it. A useful test is to count how many bars need transposition, how many lines need reassignment, and whether the ending would have to be composed from scratch. If the answers are high and the season is short, the chart goes back on the shelf. The workings of an adult vocal jazz ensemble shape that arithmetic: the number of singers, their reading level, and how much rehearsal time the calendar allows all enter into it before a single note is taught.

The limit of all of this is that a director's reasoning is rarely written down. Charts get pencilled, transpositions get annotated, and the why behind a choice often lives only in the rehearsal room. What can be read is the score itself, and the arrangement article is a clear place to start learning what all of those marks are doing. For the people who play under those marks, directors and rhythm sections in choirs follows what the piano, bass and drums are doing while the voices sing.