It starts with a few irreverent tickles. Just three minutes into Bird’s “Au Privave,” Brad Mehldau gives his muse the green light, messes around with a spray of notes, and we’re off into a chatty conversation where blithe trills are grounded by buoyant thumps—meaning informality has just as much bearing on this entertaining exchange as decorum does. Perhaps that’s predictable. Impulse!’s last three Haden duet discs (with Jim Hall and Gonzalo Rubalcaba, respectively) make hay with a parallel dynamic. One of the bassist’s strengths was splitting the diff between the formidable and the folksy, and as these six performances from a 2007 German show illustrate, Mehldau has little problem turning to his colloquial side when the mood strikes.
The cozy context gives the pianist’s whimsy more wiggle room than usual. Though the book is ballad-heavy and the tempos measured, both participants skip through a handful of passages with a mischievous air. Mehldau’s right hand dodges opaque excursions and lets light-hearted flurries carry the day on “What’ll I Do.” Because the two decide on a bouncy gait for “Long Ago and Far Away,” it too is a romp that trusts mercurial solos to control its temperament.