Recently a dear friend who had listened to me sing some early Italian songs asked me why I had "used" vibrato in baroque music.  Restraining the urge to pick up a blunt object to apply to his head, and the urge to scream that the vibrato controversy has been over since 1984 with Friedrich Neuman's article on "The Vibrato Controversy" in the American Musicological Society's journal, I said to him gently, "That's just because I'm old."

Now granted that I do have a wobble nowadays, and I must say that it's mine and I've earned it in forty years as a singer.  I am not prepared, however, ever to agree that straight tone singing is ever, ever appropriate in any period of music or any genre unless some crazy 20th century composer has specified it.  I know that most of us who were trained in the 1970’s were told that it was the right way to sing baroque music, and I know that choral directors and recording engineers like it because they like the simpler pitch, but it’s just wrong.  It is unhealthy singing, and no singing treatise of the 18th century or before ever called for it.  Neither did any 19th century voice treatise celebrate a new technique of vibrato!  Rather all those voice masters required a vibrant tone.  The violin treatises, yes, called for no constant vibrato but NOT the singing treatises.

According to most voice scientists whose work I’ve read, vibrato is the result of a larynx that is operating in a healthy manner without muscular constraints interfering with its function.  It is a normal result of healthy singing.  Yes, singers can add a wider pitch variance if they want to do so.  Yes, singers often have the wider pitch excursion when they sing heavier late Romantic and 20th century styles, but not doing these things does not result in straight tone.

My understanding of straight tone singing is that it happens either when the singer is producing such a small sound that the larynx is barely functioning or when the singer is singing a fuller sound but using the muscles around the larynx to hold the larynx still.  That constraint upon the larynx is generally considered to be unhealthy and unsound practice.  There are voices that have quite small pitch excursions in their vibrati, and I have heard people mistake such voices as coming from singers singing without vibrato.  Not so! 

Usually the singer singing without vibrato is singing out of tune.  Once an acquaintance who is an early music fan came up to me after a stunning performance of Hildegard’s Ordo Virtutem.  She hoped that now I realized how much better people sounded when they sang without vibrato.  My mouth dropped open, and that time, too, I refrained from asking her why she still had not read the literature.  The only person in that show who had sung a vibrato-less sound was the one who was out of tune through her whole part.  The lead in the show was the wonderful Shelly Cohen, who is far too well-trained a singer to sing without vibrato.  She had then, and probably still does have a silvery lyric voice that does not have a wide excursion, but does have a healthy vibrato.

A normal healthy vibrato occurs at a rate of 5-7 cycles per second with an total excursion no more than a half-step.  That is to say, the excursion is a quarter tone or less on either side of the pitch.  A wobble, like the one I have nowadays, is often slower and wider.  When wobbles occur in young singers, most voice teachers think that those singers have abused their voices.  In someone my age, it is to be expected.  Vibrato is not the same thing as a wobble.  Wobbles are bad; healthy vibrato is good.