"I just want to relax the spines of dhrupad listeners," says Faiyaz Wasifuddin Dagar in the liner notes to one of his albums. "It's not necessary that you understand music to enjoy it." Dagar, for his part, understands dhrupad intimately--he's part of a family that's been playing the ancient form of Indian classical music for 20 generations. Dhrupad is considered austere in comparison to more modern styles, which employ acrobatic techniques or richly ornamented melodies, but it can be just as dazzling--at its highest level the singer enters a trancelike state. On Dagar's Dhrupad (Sense World Music), released earlier this year, he crafts a constellation of sounds. For the introduction, or alaap, a luxurious investigation of the raga's tonic, he sings low-pitched, wordless utterances of varied modulation; from there he moves into a high-powered, rhythmically devastating extrapolation of the raga's text, most of which is rooted in Vedic chant, singing in a gorgeous, pure voice and making each syllable sharp and clear even when the notes seem to zigzag like a pinball shuttling wildly between bumpers. For decades Dagar's father and uncle, Zahiruddin and Faiyazuddin, performed in a duo format called jugalbandi, as do today's other leading dhrupad singers, the Gundecha Brothers. The duo setting requires intense focus and an almost telepathic connection to keep the hypnotic improvisation in sync, but a solo performer like Dagar doesn't have it any easier--he's essentially working without a net, without a partner to feed him fresh ideas. Top-notch dhrupad singers are rare, and Dagar doesn't make it here often; his last Chicago performance was in 2000. He'll be joined by Mohan Shyam Sharma on the pakhawaj, a double-headed clay or wooden drum that predates the tabla. Wed 11/9, 7 PM, Preston Bradley Hall, Chicago Cultural Center, 78 E. Washington, 312-744-6630. Free. All ages.