Yandrew plays Friday, May 1, at The Shed in Durham. Skylar Gudasz opens. The 9 p.m. show costs $5.

In the vast open space between jazz and classical music, it can be tough to speak with specificity. You either describe the music in terms more poetic than informative, or you namedrop the influences you detect: Cecil Taylor or Charles Mingus maybe, perhaps John Zorn or Uri Caine.

But on their debut LP, Crossing Streams, the improvisational duo Yandrewdrummer Dan “Yan” Westerlund of Bowerbirds and Canine Heart Sounds and cellist Drew Anagnost of Lost In The Treesstake out a small, clear territory within that wide musical realm. They do it by finding and finessing a formula. For each of these nine instrumentals, Westerlund and Anagnost deploy the same basic plan: Open with a groove, let it play until it’s about to lose energy, move into a second groove. Most pieces change focus near the halfway mark, just as the opening passage starts to become too repetitive. The variation comes in different musical textures and in which instrumentalist is leading the way.

Given this template, “Thorzuul” may be the quintessential Yandrew tune. Anagnost’s cello establishes a bright field of sound, and Westerlund’s drums cavort in it. Westerlund then hands the lead to Anagnost, who quickens the tempo and drapes his cello in fuzz. This new edge makes his bowing sound like power chords, as if he were using sheet metal instead of horsehair.

While Westerlund deploys an impressive variety of drum sounds, Anagnost rarely dazzles with chops. Instead, he shows virtuosity in the alien sounds he gets from a familiar instrument. In “Badiddily-Do,” his octaves are round and hypnotic. For “Hers,” the cello sounds like it’s stuffed with silt. The double-tracked cello of the title number even sounds like a wind instrument, something an eastern mystic might use. Westerlund elicits ritualistic creaks and screeches from his cymbals as the piece gathers a raga-like momentum. The last section blossoms into a wonderful, gamelan-like din.

The closer, “Wendy,” at last breaks the pattern with Yandrew’s most song-like arc. Anagnost opens with a happy, arpeggiated dance that builds into a romp and mosh. The discord never obscures the sweetness of the affectionate, sincere dedication. It ends with the sort of familiar murmur one’s partner might make as they’re falling asleepa suggestion of the surprising intimacy and accessibility of this admittedly outsider music.

Label: Self-released

This article appeared in print with the headline “Pair varietals.”