One can always anticipate originality from Carla Bley. And she doesn’t disappoint.

Admired by other composers as wide-ranging as Tom Harrell and Gary Burton, Bley’s originality springs from her powers of observation and her intent to convert naturally musical sounds to the framework of appropriate meters, of notatable forms and of instrumental pitches. Burton shares this naturalism by freeing the vibraphone to attain more vocal expression. So does Harrell, who draws inspiration from the sounds he hears even as he walks down the street.

A case in point: Carla Bley’s “Sidewinders In Paradise” grew organically into an amalgam of Lee Morgan’s “Sidewinder” rhythm, the chirps and blurts of birds and frogs on a Caribbean island, and a not-too-subtle reference to the kitschy tune, “Strangers In Paradise.”

Likewise for “Baseball,” which, sure enough, taps Larry Goldings’ unconventional approach to the organ for an evocation of ballpark schmaltz and energy heightened by the underlying excitement of the sport. Interestingly, Bley had gone to just one baseball game in her life before writing this tune.

Yes, Bley’s 4X4 band does include organ and piano, which ordinarily would engage in a collision course. However, Bley pulls out of each keyboard instrument its strengths as complements rather than competitors. On “Les Trois Lagons,” Bley does the honors of a slow and ruminative introduction before Goldings takes over the charge. And then, after a pause, Bley’s spare half-note motif reveals that the tune was written to the changes of “Jeepers Creepers.”

By combining such common references with the selection of individualistic musicians, Bley has made her music accessible without abandoning a personalized approach.

Paring down to 8 musicians (4X4) from her big band, Carla Bley has created yet another group which defies expectations, and which for that reason delights as well.