The dB’s this week released a new song as a free MP3 download — the rocker ‘Revolution of the Mind,’ featuring Yo La Tengo’s Ira Kaplan on guitar — and announced plans to issue ‘Falling Off the Sky,’ the band’s first new studio album in 25 years, sometime in the spring of 2012.

R.E.M.’s rare 1981 ‘Cassette Set’ demo tape — 400 copies were sent to labels, clubs and journalists — has surfaced online, giving many fans their first taste of producer Mitch Easter’s original mixes of ‘Radio Free Europe,’ ‘Sitting Still’ and ‘White Tornado.’