Vibrato Problems: (1) The Vocal Wobble: We often hear singers that have a wide and slow vibrato (see article on the vocal wobble.) The causes have been described in the article entitled "The Vocal Wobble". A wide vibrato is usually a lack of proper "resistance of the breath pressure" or a lack of "focus in the tone". It can also be a result of a lack of proper adduction of the vocal cords. One or all of these problems create a sound that our culture defines as "age in the voice". I have found that singers in their 20's can have a wobble. I have students in my studio who are in their 70's who have no sign of such a vocal characteristic. In fact, they have what our culture calls a youthful, and more importantly, healthy sound. I have found the primary cause of the vocal wobble to be misuse rather than age. An unhealthy vocal technique used over a short or long period of time can be the cause such a vocal problem. The solution is quite simple: vocalize exercises that require body support along with focus. The "ng" is a healthy sound that can help develop focus in the voice. The sustained "hiss" can help a singer learn what muscles to use in order to "hold back" the breath pressure or "support the tone".

(2) The Overly-Fast Vibrato: Some singers have an overly fast vibrato that can be as disconcerting as the wobble. Neither the wobble nor the fast-vibrato is the desired vocal sound for healthy singing. A fast-vibrato can be caused by a number of vocal situations. (1) Pressure at the root of the tongue. This pressure at the root of the tongue can have its origin at inhalation or at the attack or onset of sound. (2) Lack of vocal cord approximation: Many singers who do not quite understand that the vocal cords must close after inhalation. This lack of proper adduction of the cords can result in a faster vibrato speed. If the vocal cords do not approximate closely enough, the vibrato can become faster depending upon the size and shape of the vocal cords themselves. (3) Lack of support is another cause of this vocal problem. Most of us have heard singers with definite vibrato problems and we have experienced singers with healthy vibrato. One key factor in attaining a healthy sound is to be sure that the vibrato is vibrating at an even rate. An uneven vibrato can be caused by sudden changes in the sub-glottic breath pressure. This is caused by a lack of even "body resistance" or support in the body. The vocal cords then begin to separate and vibrate unhealthily. The result is an uneven vibrato sometimes accompanied by pitch problems. The fast vibrato is less noticeable if the rate of vibrato is even rather than sporadic.

(3) The Straight Tone: So often I have singers who come into my studio with a straight tone (no vibrato). Some of these singers are not aware of vibrato or how it is developed in the voice. Many come into my studio with the express desire to develop vibrato in their sound realizing that their voice is lacking in that particular area. In over 25 years of teaching, I have never had a singer in my studio that could not develop healthy vibrato.

Some straight tone singers have sung in choirs where the director has demanded straight tone. This is potentially a damaging circumstance. Straight tone singing is extremely unhealthy for the voice. Vocal nodules can result from such vocal production because of too much pressure held at the glottis to prevent vibrato from occurring in the tone. Choral blend is developed through vowel and acoustical alignment, not squeezing the voice into straight tone sound. The proper vowel and acoustical alignment can create a beautiful vocal blend. I experienced this personally in Berlin when 11 of my singers sang "Let Your Garden Grow" from Candide as a finale along with a men's choir. The resulting vocal sound of these 11 singers who were trained on the "ng" ring was amazing to say the least. Because these singers were trained with vowel and resonance alignment, the resulting sound was one of beautiful blend of tone along with fullness of vocal sound and blend. Several conductors from German opera houses came to me after the concert to ask about the training of these singers.

Most straight tone singers cannot use the idea of vocal cord closure during the first part of their training because "too much pressure" has been held at the vocal cords for too long a time period. I have found that vibrato comes into the voice when the singer achieves proper balance in the "support muscles" and when the singer keeps the feeling of the "u" vowel in the pharynx. The Italian "u" is a crucial part of a singer's training in order for vibrato to occur. The "u" vowel allows a healthy adduction of the vocal cords without too much pressure at the glottis. It is understandable that this vowel is crucial in the Italian School. I find that the "u" vowel must be produced without the "bunching" of the back of the tongue and with a "high and wide soft palate" in order to be efficient acoustically. The result is beauty and resonance simultaneously.

(4) Diaphragmatic Vibrato: A diaphragmatic vibrato is the pulsating of the diaphragm during a sustained tone to "create" a false vibrato. Music theatre singers develop this damaging vocal habit in order to have some sort of vibrato when none is present in the tone. This is a huge mistake. A diaphragmatic vibrato is difficult to repair because the lower abdominal muscles memorize the pulsating sensation so deeply. This situation can be repaired with lots of time and hard work. Solution: Use the idea of the sustained "hiss" and memorize what the body "feels" during this function. Then sing a tone while keeping the same "feel" in the body. This will stabilize the shaking diaphragm.

(5) The role of the vocal trill: In some cases, a singer can begin to awaken the vibrato function by using a trill. A trill is an educated yodel at the vocal cords that may or may not be easy for a singer to produce. Some connect with this idea and begin to release the "over-squeezing" of the vocal cords, therefore allowing for the development of a vibrato.

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