With Sigur Rós taking an indefinite hiatus from recording and touring (band members are busy with babies!), Jónsi, frontman for the enigmatic Icelandic outfit, is issuing his full-length solo debut, Go, on Tuesday.

The album is produced by Peter Katis (Interpol, The National, The Swell Season), and features classical arrangements from Nico Muhly (Grizzly Bear, Antony and the Johnsons). NPR has an exclusive stream of Go, and as fans might expect, it’s an exquisite work.

Jónsi recently appeared on Jo Whiley’s show on BBC Radio 1 to promote Go with a performance of the lead track, “Go Do.” But as is de rigueur for artists who visit the Live Lounge, also regaled listeners with a cover tune. Playing solo piano and with his falsetto in top shape, he turns in a gorgeous take on MGMT’s previously densely packed “Time To Pretend.”

In his on-air interview with Whiley, Jónsi mentions listening to Metallica and Iron Maiden growing up. His cover of “Time To Pretend” (and really, the sum total of Sigur Rós and his side project, Riceboy Sleeps) is a gazillion billion miles away from anything remote resembling such heavy influences. Hear here:

In addition to celebrating the release of Go on Tuesday, Jónsi kicks off his 2010 world tour, with a first leg that has him enchanting North America through early May.

Grab a free download of Jónsi – “Time To Pretend” via Stereogum.