Flute choir

A flute choir is an instrumental chamber ensemble consisting of range extensions of the flute family. Although a flute quartet can, in some cases depending on instrumentation, be considered a flute choir, most flute choirs extend the melodic range of the group in either direction with the addition of "melody" flutes. Most flute ensembles of five or more people can be considered a flute choir, although this is not a fixed number.
History.
The modern definition of a flute choir is a recent development; likewise, the abundance of literature specifically written for the ensemble has grown alongside the ensemble itself. In the 1960s, flute choirs began to surface within colleges and communities. As there was very little music available for the instrumentation, directors of the individual groups arranged and composed music for the group. Over time, these groups learned of each other. The performers' love of the flute family eventually led to the formation of the National Flute Association. In turn, this led to an increase not only in music written for the flute and flute choir, but also to an increase in flute choirs. As the literature for the ensemble expanded, more flute choirs began to form.
Instrumentation.
The following instruments, listed by descending range, can be included in a flute choir:
The flûte d'amour in B or A is also occasionally seen in flute choirs. The G treble flute is used predominantly in the modern flute choirs of Scotland and Northern Ireland. 
The most common instrumentation for a "standard" flute choir can be seen in much of the literature:
and by the mid 2010s, many of the well-established community and professional-level ensembles have acquired at least one contrabass flute.
As some groups do not have access to the larger flutes, some alterations are usually provided. Alto flute parts are usually accompanied by a transposed part for the concert flute (usually including certain octave changes because of the extended range of the alto). The sheer cost and limited availability of flutes lower than the bass flute usually prevent most community-based flute choirs from performing these works. However, many flute choirs use the lower voices of the string section (cello, double bass) to cover these lower parts.
Repertoire.
While most of the initial music arranged for flute choir included little more than transcriptions of classical pieces for orchestra and chamber ensembles, in recent years many new compositions have been created by such active composers as Ian Clarke, Sophie Lacaze, Phyllis Louke, Catherine McMichael, Ron Korb, and Judy Nishimura, Doina Rotaru, among others. Although flute choirs are still a relatively new ensemble in the history of music, much of the established repertoire is available at many music stores worldwide, in addition to sites focused solely on the ensemble, such as ALRY Publications and Flute World