Full Disclosure: many of the samples I share in this article are from the See-A-Dot Music Catalog, a company for which I am the director.
Unlike many aspects of the experimental music world, choral music in the western classical realm has historically avoided employing a variety of vocal timbres in any given piece, usually defaulting to the inherited English choral cathedral tradition. By contrast, string players are readily prepared to perform a variety of sounds on their instruments from sul tasto and sul ponticello to pizzicato and scratch tones. But while this kind of experimentation with sound used to be unusual in the choral world, it is now becoming more common.
It’s not that choral singing as a whole does not employ a variety of timbres: singers sing differently in a gospel choir than when singing in an Anglican church; musical theater and opera choruses ask for very different vocal production, and that’s just sticking to the most common styles in the United States. If we back up even further and look at ensemble singing from a global perspective, Bulgarian choirs use an entirely different timbre from singers in West Africa, Sardinia, and India. But these timbral varieties are generally confined to specific styles and genres of music. Modern recording and communication technology has brought a new level of awareness and exposure to vocal timbre to a large group of people, and there is an increasing interest in playing with the sound possibilities of the voice influenced by music of other cultures—from yodeling to Mongolian throat and overtone singing. I believe the future of choral music will embrace timbre as an integral component of sound making.
I give credit to Meredith Monk for pioneering music for vocal ensembles that focuses on the different sounds of the voice, perhaps above and beyond the individual notes and rhythms. For example, Dolmen Music has an entire section where the soprano line gradually changes from a more open, “traditional” sound to a very bright nasal technique, and that transition in timbre is the main driving force behind the drama of that section.
Like the above example by Monk, much of this choral music is wordless, putting the focus on the voice itself as an instrument, rather than the musical interpretation of the text. Here is an example from the composer Toby Twining, who is also a versatile vocal performer familiar with a variety of techniques. Twining treats the voice like an instrument and incorporates a slew of different styles and techniques into a single composition.
While the piece certainly isn’t easy, it has been performed by college and community choirs around the country. Twining has also recently written new pieces for Roomful of Teeth, an ensemble popularizing the incorporation of techniques from global singing styles into Western music. While most of the music written for them is extremely specialized and likely not performable by large choirs, avocational singers, or even most semi-pro ensembles, there is a growing body of work that incorporates a variety of timbres and techniques in such a way that is accessible to avocational and student singers.
I’d find it silly to not include my own most performed piece for choir, which is an example of timbral exploration for choirs. Hymn to Aethon uses four different timbres, ranging from dark to bright sounds, and it’s the use of timbres and rhythmic groove that provide the bulk of the aural interest, not the harmonic content which mostly revolves around melodies and open fifths.
I believe what contributes to the popularity of this piece is the relatively simple harmonies (it’s only 4 parts with almost no divisi) and straightforward rhythms making it relatively easy to perform without compromising its interest. I’ve taught this piece to unauditioned college groups and professional ensembles, and in both instances, the rehearsal process relies on rote learning, vocal play, and listening rather than note learning, blend, and lyrical interpretation. I think exploring vocal timbres will play an increasingly important role in the future of choral music as a way to expand the expressive palette available to choirs without relying on the harmonic content of the work.