After many years as a trio, The Bad Plus reinvented itself, abandoning piano and taking on a fourth member for the eponymous The Bad Plus in 2022. Complex Emotions, the group’s first release for Mack Avenue, follows an impressive run on Edition Records. It’s the second dispatch from the new lineup with guitarist Ben Monder and tenor saxophonist Chris Speed, playing songs mainly by original Bad Plussers Reid Anderson (bass) and Dave King (drums). Speed’s contribution, “Cupcakes One,” is the rockingest of the set, while Monder’s “Li Po” serves as an ethereal and abstract finale (the piece also appears on Monder’s 2024 release Planetarium, with experimental vocals by Theo Bleckmann). King’s entries are the slinky and offbeat “Casa Ben” and the lilting, almost Steve Swallow-like “Tyrone’s Flamingo,” a fine showcase of Monder’s fluid, mysterious aesthetic. Anderson weighs in with the moody and powerful “Grid/Ocean,” “French Horns,” “Carrier,” and “Deep Water Sharks.”