This is Fresh Air. I'm David Bean Kooley, professor of television studies at Rowan University in New Jersey, Infra Terry Gross.

That's Counter-tenor Anthony Rothkastanzo in the title role of the Metropolitan Opera's production of the Philip Glass Opera Ocknotten about the Egyptian Pharaoh who was married to Nefertiti.

It was a career-defining role for him. The album from the production won a Grammy this year, and next week he returns to that celebrated role at the Met Opera.

Today we feature our interview with Anthony Rothkastanzo. As a counter-tenor he sings in the range associated with women's voices.

Some of his repertoire from the 16 and 1700s, music by such composers as Handel and Mono Verdi, was originally written for Kastrati, men who were castrated before puberty to prevent their voices from changing and deepening.

Kastanzo also sings contemporary music. Terry Gross spoke with him in 2019. We'll hear Kastanzo singing in excerpt from Ocknotten a little later, but let's start with an excerpt from Philip Glass's liquid days.

This is from Kastanzo's album ARC, which came out in 2018 and features him singing music by Glass and Handel.

The song is called The Lounge. Love has an answer for everything. Love's spice gently, and crosses its length when you are.

Here we are. Here we are. Sleep, sleep, sleep. Sleep, sleep, sleep. Sleep, sleep. Sleep.

Anthony Rothkastanzo, welcome to Fresh Air. You're amazing.

Thanks for having me, Terry. I'm thrilled.

Let's start with what does it mean to be a countertenor?

A countertenor is essentially a man who sings in a falsetto voice, and the falsetto voice is just particularly resonant and well-developed, and it's that simple.

What's the difference between what you do and what Smokey Robinson does?

Well, actually, we do the same thing physiologically, so every person has these two vocal cords, and they come together.

I sort of liken it to blowing grass between your thumbs if you've ever done that, and it makes little buzzing sound.

You blow air between these vocal cords, and they buzz like a kazoo wood.

And if we had no head, that's all it would sound like.

But the kazoo sound travels up into our bone structure and our face, and within our mouth, and it takes shape, it takes color, it takes volume bouncing around in there, and it comes out as sound.

And as opera singers, we learn to sort of use that air and those resonating spaces with the utmost finesse.

There are also, of course, muscles involved. There are 60 muscles in the throat.

So as a countertenor, we're bringing the vocal cords together, but we're only bringing a portion of them together, say two thirds of them together, leaving a little space for some extra air to escape.

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