ArtsJournal has a link to a tantalizingly short essay in the Science Times section of The New York Times about vibrato (“Thrills and Trills” by C. Claiborne Ray). According to the article, which is actually based on findings in a 2006 study published in the Journal of Voice, pop singers’ vibrato varies more in amplitude whereas classical singers’ vibrato varies more in pitch and that “the ideal classical pitch component [varies] by no more than a semitone around the main note.” Ray, however, also acknowledged that to “teach singers to achieve a vibrato without exaggerating any component is controversial.”
For many people who grew up with the ubiquitous sounds of pop vocals, the standard vocal technique of classical music sounds artificial and can be extremely off-putting. And yet the vocal production in popular music also has its share of affectation. In fact, my earliest exposures to rock vocals were far more unpalatable to me than my first exposure to opera. And unless the vibrato is really out of control—I’ve heard singers oscillate on intervals as large as minor thirds—I have no problem with the use of vibrato when singing in a foreign language and backed by a large orchestra. But I’ve never been a particular fan of classical vibrato in many other areas of the repertoire. I still remember my negative first encounter with the music of J.S. Bach when I was in eighth grade, hearing and watching a televised performance of the St. Matthew Passion by a large orchestra and chorus using vibrato with abandon. I had yet to have my epiphany with classical music and I found the sound of the music to be overblown and overwrought. I only warmed up to Bach, and in fact subsequently became a lifelong devotee, after hearing period instrument performances with pure tone singing.
But perhaps where vibrato can be the most problematic for me as a listener—and I know I’m treading on hallowed ground here—is in the realms of sung American English and in more complex contemporary music, whatever the language of the text. Vibrato makes it way more difficult to understand English, a language which I’ve heard classical vocal teachers describe as “unmusical” due to its emphasis on consonants over vowels. Yet English inspires a very different type of music and many composers have addressed this issue by creating vocal lines which emphasize the consonants. To sing such lines with heavy vibrato seems counterproductive.
And then there are the strictly musical concerns. For music where pitch specificity is extremely important, e.g. serial music, a variance of a semitone can be extremely disorienting. And in microtonal music, such a variance completely interferes with the perception of the intervals. Many listeners hearing vibrato-laden performances of contemporary works walk away from them making claims that such-and-such composer doesn’t know how to write for the voice. I would counter that perhaps it’s because such-and-such singer’s technique doesn’t effectively serve the music. Everytime I’ve heard such comments made about Babbitt and Carter it made me wish I had a boombox so I could blast Tony Arnold’s remarkably idiomatic performances of their vocal music, performances in which not only every interval, but also every word of the text that was set, is clearly discernable.
All that said, many composers of highly complex vocal lines sung in English are thoroughly satisfied with a performance filled with pitch oscillations. In fact, many claim it makes the music more emotionally engaging which I find utterly baffling. Sometimes it has been extremely difficult for me to get the vocal qualities I want from singers who have performed my own music—which is invariably in English and which derives its form from pitch specificity. When I have worked with singers directly, it has usually turned out fine, especially if I demonstrated the sound I had in mind. But writing “please no vibrato” over a score can be perceived by a stranger as an uninformed affront to serious vocal production, so it’s something that I avoid doing. I also want the singer to feel a sense of ownership of the music, which any kind of overt decree seems to discourage, because it is ultimately when a singer makes the music his or her own, no matter what the technique, that leads to a satisfying emotional engagement.