A trombone choir is a musical ensemble comprised mostly, if not entirely, of trombone players. The choir normally has at least three parts including first and second trombone and bass, but this is not a hard and fast rule. As trombones are brass instruments, these groups are a specific type of brass ensemble.
These groups do not have a specified size, but the term "choir" generally means at least two performers per part, with the connotation leaning to larger numbers. The number of players depends on both the instrumentation of the work to be performed and the preferences of the trombone choir director. Unless the choir is brought together for a specific event of considerable significance where more players are desired for power and overall impact, groups of 25 to 50 are common. This is not unlike other ensembles.
A trombone choir most commonly features tenor and bass trombones. In some cases, however, they might also include alto trombones. In very rare instances, soprano trombones also might be present, and some choirs add a tuba or two to help solidify the bass line or blend tone. Composers may use peripheral instruments such as percussion in trombone choir compositions, but the number of peripheral players usually doesn't come close to the number of trombonists.
One of the most frequent places a trombone choir is found is in colleges and universities. These groups are founded by the brass departments of the institution's school of music, and are often conducted by the professor of trombone. Academic trombone choirs give trombonists an opportunity to hone ensemble playing skills while simultaneously earning credit toward a music degree. Even though the players are still students, they can produce concerts of exceptionally high quality.
If a trombone choir is not established in an academic setting, professional trombonists, music educators and trombone enthusiasts might form one. These choirs are designed to showcase the abilities and sounds of trombones. Sometimes these choirs even step into a recording studio to make CDs and individual tracks. Although the choirs might earn some payment for performing or from recording sales, usually they are volunteer-based, with performers playing simply for the love of trombone music.
The sound of a trombone choir can vary greatly. This is because so many different models of trombone are available, and because the trombone is capable of producing everything from sweet, mellow melodies to raunchy growls and slides. The number of players also matters, with large trombone choirs being capable of producing nearly overwhelming volume. A good trombone choir director, however, is able to mentally conceptualize the sound he wants the players to produce and get it through both technical explanations and imagery.
A shortcoming of trombone choirs is a conspicuous lack of available music. The trombone choir is not an ensemble upon which composers have concentrated seriously on a wide scale. Subsequently, much of the music trombone choirs play include commissioned pieces or arrangements of pieces intended for other instruments or ensembles. It is common for arrangements to come from the trombone choir directors, who find music they like and work it out for their specific needs. The irony of this is that, when coupled with the versatility of the trombone, arranging means trombone choirs can play everything from Bach to Bill Joel and television or movie themes.