To those who have heard of it, the autonomous Russian republic of Tuva is chiefly known for three things: its colorful and highly collectible stamps, its rugged terrain (this was the place chosen by fly-fishing Russian Prime Minister Vladimir Putin as the backdrop for a much ridiculed series of photos in which he appeared shirtless and on horseback) and its khoomei, or throat singing. In characteristically paranoid fashion, the Soviets regarded khoomei as subversive, and spent 50 years attempting to suppress it, but this ancient folk music proved considerably more resilient than the U.S.S.R. and thrives today — a favorite on the world-music festival circuit and on the CD players of fashionable, Eastern spas.

Rizzo has worked with the likes of Coldplay, k.d. lang, Alanis Morissette and Paul Oakenfold, and brings to the project all the consummate, knob-twiddling expertise that you would expect of a two-time Grammy nominee. Huun Huur Tu's sparse, ethereal songs — where simple lutes like the doshpuluur and two-stringed fiddles like the igil form the typical accompaniment — are fleshed out with drum loops, cello, keyboard and guitar, but they are not overwhelmed. In haunting paeans like "Mother Taiga" or "Ancestors Call" the romance of the Tuvan steppe is potently concentrated.

That makes Eternal rather too stirring to do duty as a soundtrack to a massage or dinner party, so save it for when in a cosmic mood. Pour a glass of something, close your eyes and let your soul soar through those boundless Tuvan skies. If these rousing sensations inspire you to strip off your shirt and strike macho poses while straddling a horse, well, fine. But we recommend you keep the photos to yourself.