Heart Tonic opens like a Jefferson Airplane or Soft Machine record—with long, eerie, psychedelic organ tones. It ends like West African funk, with a slippery bass leading interlocked 9/4 rhythms. Between these brackets is knotty, complex postbop that doesn’t sit still long enough to be described less broadly. Fortunately for alto saxophonist Caroline Davis, her music is even better than it is audacious.

The aforementioned organ freakout (courtesy of Julian Shore) at the beginning of “Footloose and Fancy Free” lasts 11 seconds before the eight-minute tune completely changes the subject, shunting into an anxiety- and Rhodes-driven convolution that Davis and trumpeter Marquis Hill navigate steadily. Tension further mounts on “Constructs,” a long piece that changes tempo, key and character often and suddenly; Davis and Hill’s shared combination of warmth and daredevilry is its through line. Davis in particular has such a warm, rich alto tone that it often sounds like a tenor being played in its upper register, as on the album’s lovely highlight “Fortune.” The track also features a long, sublime upright solo from Tamir Shmerling and excellent organ work by Benjamin Hoffman, who adds subtle color behind Shore’s supple piano. Drummer Jay Sawyer gets a thunderous turn on “…TuneFor,” a coda to “Fortune” based on one of its motifs.

Sawyer keeps busy on this record of many rhythms, a project often based on the human heart and/or Davis’ father’s arrhythmia (though you may have to be a cardiologist—or Steve Coleman—to make sense of these concepts). Shore, too, significantly shapes the music, working two synthesizers (best heard in the weird ostinati of “Dionysian”) as well as his piano and Rhodes. But Heart Tonic remains Davis’ triumph, a gauntlet of complex, often fraught music that remains approachable. It’s the finest album yet by an artist who has many fine records ahead of her.

Preview, buy or download songs from the album Heart Tonic by Caroline Davis on iTunes.

Read Aidan Levy’s profile on Caroline Davis from the January/February 2016 issue of JazzTimes.