“Prelude in the Ash,” the first ballad off trumpeter Ambrose Akinmusire and guitarist Mary Halvorson’s Slo-Mo Neon Luminate Hoverings, starts nimble and intimate: Akinmusire’s sentimental phrases could soundtrack scenes of pouring rain in a film noir. Halvorson joins with a rocky arpeggio that occasionally summons her signature glassy pitch bends, balancing Akinmusire’s assuredness with a sense of timidity. The piece is fairly straightforward, but the artists’ different tonal approaches turn the jazz ballad away from obvious readings like “sad” or “romantic” and toward ambiguous, multilayered feelings. Unstable textures are the focus of their compositions here; the soundscapes they create are ready to swerve at a moment’s notice.
While this is the duo’s first collaborative album, the two avant-jazz stalwarts have built a rapport over the past decade. Their paths have mostly crossed in larger group settings, like on Halvorson’s 2018 album Code Girl, and during a 2016 trio residency with pianist Craig Taborn at Roulette. Slo-Mo Neon Luminate Hoverings is a more reserved affair featuring four songs by Halvorson, four by Akinmusire, and one co-written piece. The music is mostly slow and chilly, fit for a desolate retreat in a snowed-in cabin.
Their album feels like a how-to guide for all the ways a simple note can be warped. Halvorson’s transfixing use of delay effects has become one of her signatures, and she uses the duo setting to explore even further. The beginning of “Nice to meet you again for the first time” is my favorite of her adventures here: The dry signal of her guitar is bare and tinny, appearing just a millisecond before the processed tones pass through her amp. Hearing the notes both before and after the effects gives the illusion that we’re sitting in the room with her, a closeness otherwise hard to capture.
The most challenging textures happen when Akinmusire noodles with the delay pedal. On “This Vivid,” he loops shouts that combust and glitch around Halvorson’s pointillistic playing. The echoed screams take an unnatural shape, but the guitarist’s barrage of notes shows her awareness of how and when to push back. You can tell from the quick decisions they make that the musicians are bringing out the best in one another.
Duo settings are often bare-bones affairs, but Akinmusire and Halvorson wring timbres from their respective instruments that make further players feel unnecessary. On “Watersmoke,” Halvorson’s picked notes lag with percussive detritus, forming natural rhythms like air bubbling to the ocean’s surface. At times, the notes elongate and crescendo like a lap steel. Akinmusire similarly manipulates the attack of his instrument on “Soundcheck.” The premise is simple enough: After his virtuosic intro, he stacks individual breathy notes like an a cappella group warming up. The looping of his horn gives it a consistent, uniform attack, sounding more like an organ, with its immediately grand profile. The maneuver is more fun than deceptive, a clearly synthetic orchestra that Akinmusire lacerates with bebop-style phrasing. He builds the wall and tears it down all by himself.
Lots of contemporary atmospheric jazz seems intended to induce some kind of faux meditative trance. It’s circular, light, and airy, modeled after new-age music and spiritual jazz aesthetics. This is the rare addition to the atmospheric jazz canon that revels in the way one off note can fuck up your entire mood. When the duo approaches a pensive motif, it folds, shatters, and breaks before transforming into a new subterfuge. On Slo-Mo Neon Luminate Hoverings, Akinmusire and Halvorson are in control of all the moving parts: They might let the pieces hang here and there, but anytime they seem to sit too comfortably, they point them in unconventional directions.
