In the mid-1980s, San Francisco-based Paul Pena--a black blues singer/guitarist best known for writing the Steve Miller Band hit "Jet Airliner"--was listening to shortwave radio when he came upon a broadcast of "throatsinging," a vocal style from the tiny region of Tuva, then part of the Soviet Union. The technique enables a single singer to produce multiple tones simultaneously, thus harmonizing with himself. With barely any resources to work from, Pena figured out the method, becoming so proficient that he was invited to participate in Tuva's triennial throatsinging competition. Pena, blind since birth, made the trip accompanied by some associates and documentarian brothers Roko and Adrian Belic, where he charmed Tuvan audiences and won his division in the contest. It is not too much to say that Genghis Blues, the Belics' record of this excursion, is utterly irresistible and, for its first two-thirds, uplifting. (A series of catastrophes darkens the last part of the trip.) The travelogue aspects, the music and culture, would have been enough, but holding everything together is Pena, a complicated personality whose huge talent for, and joy in, music is mixed with a well-earned bitterness over the Job-like misfortunes that have marked his life. (Those misfortunes have only multiplied since the film was made: See www.sfweekly.com/, an update to a long feature about Pena and the film.) The Belics organize their already-rich material for maximum effect: It's hard to imagine any music or documentary fan being less than enthralled by the whole.