After dozens of columns dealing with the singer’s voice, I thought it appropriate to look at the singer’s hearing. Although a neglected subject, hearing in singers represents the other half of the vocal process, the input which is equally as important as the output.
If voice production is complex and marvelous, hearing is even more so. Its complexity and sophistication involves activity on a microscopic, even molecular level. If human hearing were any more acute (i.e. by even one order of magnitude), we could hear the random (Brownian) movement of fluid molecules bumping into each other! And the range of hearing is equally fantastic, at birth ranging up to 20,000 Hertz (vibrations per second). That approximately corresponds to a note 6 octaves above middle C on the piano. This is the realm of dog whistles and bats, and well beyond the most coloratura of sopranos.
Unfortunately, the inner ear quickly begins to deteriorate, a process that scientists have shown to commence even before birth. Audiometric testing, which examines hearing range up to 8,000 Hertz, shows in most people a gradual decline of the higher frequencies that may begin in the late 40s and continue to grow worse with advancing age. Fortunately, these higher tones are well above the speech frequencies, and are, for most people, imperceptible. For musicians and singers, however, even some loss of the higher frequencies may impact on the sounds they hear and thus upon the sounds they produce.
Singers hear their own voices in two ways: through the outer ears, as most of us do, and through the bones of the skull, directly transmitted to the bony inner ears. They also feel the voice, as the sound resonates through the breastbone and the facial bones. By these processes, they continuously adjust the pitch and intensity of the voice. By a remarkable and unconscious pitchmemory, a singer can immediately copy a sound by appropriately positioning the vocal folds and the rest of the vocal tract. This pre-phonatory posturing is essential to the singing process, otherwise one would have to find each note by trial and error!
There are two kinds of hearing loss. In conductive hearing loss, sound can not be conducted properly to the inner ear. Obstruction from ear wax and fluid in the middle ear due to eustachian tube blockage are two common causes of conductive hearing loss. When the problem is primarily in the nerve endings of the inner ear and auditory nerve, the deafness is called sensory, or sensory-neural. Aging or noise exposure are common causes of sensory deterioration. With conductive hearing loss, although sound from the environment is heard less well, sound conducted through the facial skeleton seems overly loud. This can be disturbing to the singer, who now hears the voice mostly in one ear. After flying with a cold, it is not uncommon to have such conductive hearing loss due to a blocked eustachian tube. With sensory hearing loss, the singer will not hear some of the overtones of the voice and may try to compensate unconsciously by altering voice production. Unilateral hearing loss is more disturbing than a bilateral symmetrical change, since a difference of more than 10 decibels between the two ears throws off our sound localization in 3 dimensional space. Even a slight unilateral hearing loss can cause difficulties in determining the location of a sound source, particularly in a noisy environment.
If you suspect you may have a hearing loss, the first priority is to identify the kind, and degree of loss. If it is related to excessive noise exposure, the ears must be protected from further noise trauma by the use of ear protectors.
In general, conductive types of hearing loss are often treatable, by medication or surgery. The treatment may be as simple as a course of decongestants or a nasal spray, or may involve microsurgery of the middle ear. Sensory-neural hearing loss may, if severe enough, require the use of hearing aids. In the last few years, there has been a revolution in hearing aid technology, both in terms of sophistication and miniaturization. I have treated several well-known singers who use hearing aids successfully, and this option should not be discarded out of hand based on childhood memories of grandpa’s antique device. The important thing is to be aware of your hearing status, since even subtle changes in auditory perception can affect the quality of your vocal output.
DISCLAIMER: The suggestions given by Dr. Jahn 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.
