I was sitting close enough to Justin Vivian Bond, performing at the ArtsCenter in Carrboro last month, to look into her mouth and marvel at its unbolted reveal, its size, its fearless ability to stretch open.

Her throat curled around the cries, rasps, whispers and stops of “22nd Century,” a Nina Simone song she covers on her new album, Dendrophile. Working the larynx with teeth, tongue, diaphragm and lungs to shape air, she sang, “Gods and goblins walk this land … when the soul is gone and there are no more babies being born … when there is no one and everyone.”

The lyrics evoke a future full of catastrophe and possibility, but I was struck by something deeper than her words.

Rather than eliminating the nasal sounds from her instrumenta quality of voice often described as “requiring correction”Bond jubilantly exploited her lisp and whine. Her voice begins deep in the stomach’s basement. Then she effortlessly sends it elsewhere across gender lines: husky to sweet, shrill to booming. She evokes her own Wicked Witch version of “What a world! What a world!”

Bond described herself as a blend of Aleister Crowley’s dark sorcery and Peggy Lee’s glamour. Both figures had extraordinary lives full of razzle-dazzle. Crowley was pronounced the “wickedest man in world,” perhaps partly because he revolted against social and religious norms. And in a way, so is Bond by her melding of male and female, masculinity and femininity, through music.

What is it that makes gender-ambiguous voices so different and appealing? Bond has earned critical and popular acclaim, winning an Obie Award in 2001 and a Bessie Award in 2004. She was nominated for a Tony Award in 2007. Sandra Bernhard describes her as an “electric soul” and a “modern-day shaman.” This year, Carl Swanson of New York magazine wrote a questionable feature story on her, misrepresenting Bond as a chemically castrated man with an “ambition to be both sexes at once.” She, like so many, is variously portrayed as a virtuoso and a “freak,” an angel and a monster.

There is a long history to viewing the androgynous voice with both adulation and suspicion. In opera, the castrato was a male soprano or mezzo-soprano voice popular in the 17th century. They were not falsettos, but true sopranos able to create the necessary modulation in their voice. As castrati reached greater fame they became reviled as sexual deviants. Their seraphic voices went from “ecstasy to the ear” to “grotesque seducers of men.”

In a recent play by Jorge Kuri, Monsters and Prodigies: The History of the Castrati, castrati are described as “sacred monsters whose voices were surgically molded, representing a peak of artistry.”

Following a papal edict, the surgical practice of castrating young boys fell out of favor before the end of the 19th century. However, Radu Marian and Michael Maniaci are contemporary male sopranos. Atypical hormone production and larynx development give these singers Renaissance voices. When you listen to their singing, there is a little shock, as if to ask, “Are you a man or a woman?” In interviews, they both tell stories full of trial and tribulation.

There are many other examples of singing beyond some “normal” range. A recent surge in falsettosItalian diminutive of falso, “false”has appeared in indie rock, a genre often defined by a youthful, white masculinity. Bands like Passion Pit, Wild Beasts and even Sigur Rós play with the floating, ethereal sound of falsetto. Hayden Thorpe of Wild Beasts says, “Singing in falsetto comes from a willingness to be unhinged.”

The gender-ambiguous voice is unrepentant, a queer mixture of the sexes, “monstrous.” Monster comes from the Latin monstrum, meaning an aberration within the natural order. In other words, the so-called monster defies categories. Not surprisingly, what we call monsters are often only reflections of our most profound terrors and desires. Less obviously, monsters reveal the fact that we each contain something of the other; elements of “you” lurk within “me.”

And with the hermaphroditic, we are reminded that even in our differences, we all possess male and female attributes. Writing about Michael Jackson’s violation of the rules governing racial and gender identity, James Baldwin offered that perhaps what is truly monstrous is not ambiguity but the fight against androgyny in an effort to reinforce conventional gender roles. What is terrible is a restrictive gender regime; a terrorist is someone who polices the borders of gender.

When I listen to the sensual sighs of Chris Colfer of Glee or the breathy squeaks of Little Jimmy Scottin recent years he has come out as intersexor the yawning groans of the Polish blues singer Magda Piskorczyk, I am invited. I feel surprise and discomfort, but also passion in their vibrato. Passion because their ambiguity is a constant suggestion of sex, sexed bodies, pleasure. There is suspended sexuality in their music.

Even among other animals, music plays a role in attraction and enticement, sexualizing bodies. I hear it in my backyard, the “purdy, purdy, purdy . . . whoit, whoit, whoit, whoit” of the nesting cardinals. Listening to older birds, young males and females teach one another their sweet whistles, improvising and modifying. As they build their acoustic territories with metallic chirps, showing off their skill, they are also seducing. All this activity isn’t just for reproductive purposes; the calfbird or capuchinbird is known to woo members of the same sex with a droning grr-aaa-ooo, sounding like a chainsaw in the distance. Curiously, birdsongs not only mesmerize members of their own species, but they also beguile across species. Animal songs, human and otherwise, are invitations.

The singing of Grace Jones, Bülent Ersoy, k.d. lang, Antony Hegarty and Tomotaka Okamoto makes me feel on the verge of something new, something yet to comedirection without destination. These singers reframe our sexed and gendered nervousness so that we might newly feel and make sense of our nerves. They involve us within the limits of the stage, allowing us to encounter the frightening excitement of sex and desire, but without overwhelming us.

It may be that we can never totally embrace our monsters, our fears or our rejected selves. Vampires and crones have been resilient over the centuries. And even if we could, monsters are wily. Pursued, they become something else or someone else. I am not saying we shouldn’t tryin fact I think we have an obligation to try. But I am saying that at best we can know the realm of our leviathans so we can be aware of their reappearance. And occasionally we find our witch on the stage.