Clarinet choir

A clarinet choir is an instrumental ensemble consisting entirely of instruments from the clarinet family. Typically it will include E♭, B♭, alto, bass, and contra-alto or contrabass clarinets, although some pieces are scored for a smaller set of instruments.

Natalia Forrest writes on her web site:

The sound has been described by some music fans as resembling a concert organ. Popular across the globe, choirs of clarinets play both arrangements of well known pieces and increasingly music written specifically for this type of clarinet ensemble.

There is no set number of members to a choir of clarinets. Some professional choirs, have as little as 10 members, others have up to 40.

Therefore, in practice, in total size it may range from a chamber group of five to eight or so players to a band of forty or more. Such an ensemble of instruments with varied ranges but uniform timbre may be thought of as a woodwind equivalent to the string orchestra.

In addition to these full-fledged choirs, there are clarinet trios, clarinet quartets, and clarinet quintets, usually consisting of two to four B♭ clarinets and one bass clarinet.

Composers such as Mozart, Stadler, Družecký, and Bouffil anticipated the clarinet choir in their works for three basset horns or clarinets.

James Waterson (1834–1893), a bandmaster to the Viceroy of India with a close association to Henry Lazarus and "The Military School of Music at Kneller Hall", wrote some early clarinet quartets—technically quite difficult works in a popular style—for four B♭ clarinets.

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Wikipedia