French composer Claude Debussy famously declared that “music is the space between the notes” (a quip that, in the jazz world, has also been attributed to Miles Davis). With the release of Heatmap, multi-instrumentalist Caleb Wheeler Curtis seeks to celebrate that space. Over the course of two previous leader albums, Curtis has established himself as a songwriter of great talent and complexity, penning tunes that shift, transform, unfold and surprise like origami. And yet his latest effort is a more searching affair, one that is built around his own unhurried excursions and those by pianist Orrin Evans and drummer Gerald Cleaver. To provide the album’s foundation, he recruited bassist Eric Revis, whose flickering solo through the cavernous chordscapes of “Limestone” is one of the disc’s brightest points. Each step is deliberate, each pause has meaning.