While MMW bassist Chris Wood was collaborating with his brother Oliver on their folk- and blues-based project, the other two-thirds of the avant-garde jazz trio decided to return to their roots as a Hammond organ-drums duo. In the mid-1980s, keyboardist John Medeski and percussionist Billy Martin had initially planned to record as a duo — until Wood intervened —-and 20 years later, the opportunity arose, resulting in the engaging, all-original Mago. The album is bookended by a pair of off-the-cuff free jams, “Introducing Mago” and “L’Aventura,” which are notable for their intensity and ferocity, but most of the remaining cuts are deeply beholden to the almighty groove. As usual, Martin and Medeski are able to find a number of different avenues to explore that basic beat-based framework. “Crustaceatron” has a definite hip-hop flavor, for example, while “Mojet” and the buoyant “Miss Teardrop” venture into ’60s soul jazz and boogaloo territory. The deep and dawdling “Apology” adds elements of gospel while “Bonfa” is funk with a subtle Latin flair. The playful “Bamboo Pants” blends the duo’s groovy side with its experimental tendencies to great effect.