2009, The Washington Post An eclectic selection of some recent CDs representing different facets of the 'alt-classical' sound: Alarm Will Sound: 'a/rhythmia' (Nonesuch). For their first major-label recording, this powerhouse chamber ensemble has created a kind of dance album with arrangements of music -- by Ligeti and Nancarrow, Gordon and Josquin, and many others -- that has as its common thread a strong rhythmic profile. Highly recommended. Christopher O'Riley: 'Out of My Hands' (Mesa Bluemoon). After CDs focused mainly on Radiohead, Elliott Smith, and Nick Drake, O'Riley here offers his brand of classical-piano cover treatment to songs by Nirvana, Pink Floyd, Tori Amos, and others. Time for Three: '3 Fervent Travelers.' Though the release date was moved back to January, a teaser track was made available on iTunes this week: a cover of 'Hide and Seek' by singer-songwriter Imogen Heap. The complete album includes a lot of the original music, as well as Leonard Cohen's 'Hallelujah' and, of course, the 'Orange Blossom Special.' Heritage Orchestra/DJ Yoda: Gabriel Prokofiev's Concerto for Turntables and Orchestra (Nonclassical Recordings). Sergei Prokofiev's grandson is a prominent figure on London's alt-classical scene, and the founder of this label dedicated to alternative music. His classical-meets-hip-hop concerto (sounding not quite like either) is composed in conventional movements with unconventional sounds: the soloist, a DJ, spins specially-made recordings of the orchestra. And two of several indie labels that play a role in this scene: Cantaloupe Records: Bang on a Can's recording label offers a de facto definition of the alt-classical concept: Alarm Will Sound, So Percussion, the Bang on a Can All-Stars. Recent releases include 'John the Revelator,' composer Phil Kline's powerful response to the texts of the Catholic Mass; and 'Untitled,' the latest from composer David Lang. New Amsterdam Records: This start-up label is showcasing the younger generation of alt-classical artists and composers, including the violist Nadia Sirota and the NOW Ensemble. 