PNME, it turns out, is not an acronym for Pittsburgh New Music Ensemble. Dropping in on an Internet dictionary, I was surprised to learn that it's more accurately called an "initialism," the difference being it is an abbreviation using only first letters of words; an acronym being a new word created by the first letters, syllables or even arbitrary parts of the original words.

I am not sure such a blurry distinction does much to a music lover versus a linguist, but Friday night the seven musicians and adventurous conductor Kevin Noe trafficked in initials -- performances, that is. The group presented two world premieres at City Theatre on the South Side, Amy Williams' "Cineshape 3" and Stacy Garrop's "The Book of American Poetry (Abridged)." The works show two different ways to approach a series of compositions. Garrop is in the process of writing several volumes setting American poetry, but she put stipulations on the process, such as that there be five poems per volume.

But, apparently, she also decided that the first be a poem of action and passion, the second reflective, the third quirky, the fourth short and the last searching and profound. The two volumes she wrote for the full ensemble of PNME and its outstanding baritone Timothy Jones included poems by iconoclasts such as Longfellow, Dickinson, Cummings, Sandburg and Whitman.

Sometimes the structure limited Garrop's creativity, as the two volumes seemed boxed in when some expansion for the sake of the subject matter was warranted, and the melodies, while tonal, were perhaps too tied to the text. And I am not sure why she would render the sweetness of Edna St. Vincent Millay's "Only until this cigarette is ended" by writing carnival music -- or why Jones acted drunk singing it. But many of the songs captured the poems well, especially her aggressive, stentorian setting of Sandburg's "Chicago," her wonderfully repeating of the first line of Hemingway's "Ultimately" ("He tried to spit out the truth") and the exquisite capturing of William Carlos Williams' "The Rose."

Across the varied texts, Jones displayed remarkable versatility and his tone was rich and sumptuous throughout.

Amy Williams took a much more flexible approach to her series. The only criteria for the Pitt composer's series of "Cineshape" works is that they are inspired by films. Her third is for a trio of percussion, flute and cello (originally commissioned for the Vox ensemble), each representing the main characters of the 2006 German film "The Lives of Others."

Fans probably found some fitting connections here, as each instrument took on the nature (not the plot) of the roles, such as the flute representing the Stasi policemen begins quietly but interferes more as the work progresses. But this piece worked on its own, with the musicians (Lindsey Goodman, flute, Norbert Lewandowski, cello, and David Skidmore, percussion) weaving emotionally tinged phrases around each other, sometimes creating a collection of individuals and other times, a harmonic acronym, if you will.

Williams' exploration of timbre with the percussion, with the piano's keyboard and inside frame (with cowbells placed within) was particularly colorful.

George Crumb's ""Eleven Echoes of Autumn" also uses the piano's timbre (with excellent pacing by guest pianist Conor Hanick), and the ensemble did a masterful job of letting the quiet work build in theatrical as well as musical manner, with the musicians sneaking on stage as needed.

Lastly, clarinetist Campbell MacDonald gave a space-aged interpretation of Russell Pinkston's "Gerrymander," a work for clarinet and computer generated sounds (some rather funny).

Perhaps PNME's acronym -- er, initials -- should stand for Publicly Needed Musical Ensemble, for in Pittsburgh we have little classical music in the summer, and year-round not much new music played at such a high level as Noe's group offers.