I need to get this on the record from the start: Soprano Ah Young Hong is a wonder. She has a remarkable sound and seemingly limitless technique. Her performance of the two daunting works on this disc, Milton Babbitt’s Philomel and Michael Hersch’s a breath upwards, is nothing short of breathtaking. (Get it from Amazon.) While the two pieces have a good deal in common—angular vocal lines, rhythms free from the constraint of an audible pulse, and harrowing subject matter—they occupy distinct emotional worlds.

Philomel (1964, soprano and pre-recorded tape) is Babbitt’s most famous work. With a text by John Hollander, its subject is the ancient story of Philomel, who survives grotesque mistreatment and eventually transforms into a nightingale. Hollander’s text is divided between the live soprano and the voice of Bethany Beardslee, for whom this piece and many other avant-garde classics were written, on the tape. Much of the emotional and aesthetic power of the piece comes from the tension that’s an inevitable result of the combination of the live voice and the recorded voice.

The sounds on the tape are mostly of the “bloop-bleep” school of analog synthesis, and it’s great to hear them again. They have a great deal of warmth and presence, and innova’s engineers are no doubt largely responsible for that. Ms. Hong’s performance of the is very much in keeping with the emotional tone of the piece—the music on the tape is precise, fixed like a statue is fixed in space. The sounds are cool and objective, and the voice part itself never becomes hyper-emotional, though it is full of expressive power. This is a really fine performance of a very important piece.

Hersch’s a breath upwards occupies much of the same musical terrain as Philomel, but its emotional tone is very different. Like most of this increasingly essential composer’s music, it is relentless in its expressive power, staking out and holding an intensely personal poetic space.

a breath upwards is scored for soprano, viola, clarinet (doubling bass clarinet), and horn. Inspired by the death of artist and friend Michael Mazur (whose works had also inspired the composer’s Images From a Closed Ward), Hersch assembled fragments from Dante’s Purgatorio and Ezra Pound’s Cantos. There are twelve songs, which include three instrumental interludes.

The music itself is aggressive, with long, loud chords and jagged melodies. Hersch explores registral extremes and asks his players to distort their sounds—this is never gratuitous, and when it is occasionally “ugly” it is for expressive effect. The vocal line often lays in the extreme high register as well, but Ms. Hong is always in control, and never shrill.

In this context, the relative calm of the songs in the middle of the work, beginning with the sixth (“so we had to go on the open edge”) is striking in its contrast, and the calm doesn’t last long, in any event. One of the most striking elements of this work, evident in this particular song as in many others, is Hersch’s frequent use of rhythmic unison in the instruments. It’s an effective contrast to the general use of rhythmic independence.

In addition to Ms. Hong’s great singing, the three instrumentalists—Miranda Cuckson on viola, Gleb Kanasevich on clarinets, and Jamie Hersch on horn—are of the highest order as well, responding to Hersch’s demanding score, with its exposed and virtuosic writing, with artistry and with apparent ease. For my money, this is an essential disc.

—Steve Hicken

Stream a breath upwards on Spotify: