As the rhythm section of The National, brothers Scott and Bryan Devendorf are known for elegant indie rock. But teaming with multi-instrumentalist Ben Lanz to create LNZNDRF, they eschew their regular band’s graceful drama for watery, propulsive grooves. The rubbery chug and ascending chants on “Beneath the Black Sea” recall the best of post-punk, “Hypno-Skate” luxuriates in a spacey wash of synths and “Kind Things” casts Lanz’s falsetto against a danceable strut. Spawned from a two-day improv session, LNZNDRF have unearthed an absorbing, hypnotic gem.