Ensemble singing has a long and interesting history. Most singers today began (or continue to be involved) in choral singing, whether in church, in avocational singing, or in smaller professional ensembles. Choruses vary from weekend amateur groups to highly professional, full-time ensembles where most members could just as easily have pursued a professional solo career. Over the years, I have had the pleasure of observing one of the finest such ensembles: the Metropolitan Opera chorus.
Nothing compares with the full-throated glory of a great choral performance, but from the vocal health point of view, a number of important issues distinguish choral singing from solo singing. To pursue a choral career safely and successfully, it is useful to consider some of these issues.
The first issue pertains to young (grade school and high school) ensembles. It is not uncommon to miscast young singers, based either on a too-quick assessment of their voices, or worse, on the manpower needs of the chorus. The voices of these singers are developing and often grow into something quite different from their original form. Since many future singers begin in school choruses, and often with no voice lessons except for choir practice, it is important to periodically re-audition and reassess where the voice really belongs. Many young mezzos turn out eventually to be sopranos who neglected to develop their upper range.
Assigning lower-voiced boys to sing bass when they are really baritones is even more significant. All of this may seem to be more a vocal pedagogical matter rather than a health issue, but persistently forcing the voice into a range that causes vocal strain does have health implications. As these young singers continue singing, they may carry their original label with them, often to the detriment of their vocal development and vocal health.
The main health issue with choral singing is a tendency to overstrain the voice. This involves several factors. Singers normally monitor their voices (pitch and loudness) in four ways. Air-conducted hearing picks up the sound in the air and monitors it with the ears, via the ear canals. Bone-conducted hearing is sound transmitted directly from the vocal tract through the bones of the skull and to the inner ear. Air and bone conduction are the singer’s most important feedback modalities.
Proprioception refers to mechanical vibrations in the body (such as in the mask), generated by the vibrating air column in the vocal tract. And finally, there is position sense, transmitted by spindle receptors in the muscles of the larynx. This is the least important in terms of ongoing monitoring of the voice, but it does tell the singer how to position the larynx to produce a certain sound.
For choral singers, this monitoring system is significantly impaired. Surrounded by other singers, they lose air conduction—their ears hear the voices of the others rather than their own. In some ways this is worse than not hearing at all, since the information is misleading. A false stimulus reaches the ears, one that the singer must actively ignore.
Bone conduction of sound becomes the main monitor, but bone conduction is 50 percent softer than air conduction. This is why singers may plug their ears to hear their own voice. Choral singers need to mentally recalibrate, ignoring the sea of sound around them and relying on bone conduction and skull vibration as their guides.
The conductor, who is waving and animatedly mouthing the words, is another distraction. This visual distraction is a good example of “cross-modality masking,” a visual stimulus that interferes with the ability to concentrate on hearing.
The medical implications of this are simple: the choral singer, flying by automatic pilot, may oversing. Proprioception (vibration sense) is not nearly as accurate a guide to pitch as actual hearing, so intonation may become an issue. Vocal strain, and possible damage, may be the result.
Straight-tone singing is particularly difficult. It is less forgiving in terms of pitch matching with the rest of the choir. The fine pitch adjustments a singer must constantly make in real time are more easily hidden in a vibrato. Holding a straight note versus the alternating contraction and relaxation of a vibrato also has implications in terms of muscle strain.
The final point is simple but important. Every choral performer is within the “zone of contagion” of six to eight potentially infected fellow singers. The cold virus travels by aerosol droplets, through the nose and the mouth. While singing, we breathe mostly though the mouth, bypassing the nasal filter. The best way to address this hazard is probably to stay home when you’re sick, and hope that your fellow choristers extend the same courtesy.
DISCLAIMER: The suggestions Dr. Jahn provides in these columns are for general information only and not to be construed as specific medical advice or advocating specific treatment, which should be obtained only following a visit and consultation with your own physician.
