One-third of everybody's favorite avant-groovemëisters Medeski, Martin & Wood is on holiday, but John Medeski and Billy Martin are still hard at work. They've been together for nearly 20 years, and. for their debut duo session, Martin is at the drum kit while Medeski sticks to the Hammond B-3 organ. Thankfully, the ambiance of Mago gives equal heft to both Martin crackles and crashes like a force of nature, and Medeski lays down slabs of dynamic, opulent, and mercurial vitamin B-3. Although some tracks, such as the funk-injected cooker "Mojet" and the mutant-Latin strut "Bonfa," indeed recall the earthy, robust soul-jazz aspects of the mothership band, much of Mago finds Martin and Medeski unreservedly kicking out the jams with virtual rock 'n' roll/hard funk abandon. There's a wild card or two here on songs like "Crustaceatron" and "Bamboo Pants," which feature whiffs of reggae and dub. Yet tunes such as "L'Aventura" and the aptly titled "Thundercloud" find Medeski using some spiky, free-energized lightning à laDavid S. Ware, with Martin raging like Rashied Ali on the John Coltrane masterwork Interstellar Space. If you're in need of an invigorating, heartening jolt, Mago is the tonic that will set you straight.