Before Ori Kaplan co-founded Balkan Beat Box, he was a working New York free-jazz saxophonist. He started on klezmer clarinet in Jaffa at age 11 and began his jazz study in Israel under bassist and teacher Stu Hacohen, then moved to New York at 22, in 1991, to attend the New School of Jazz. He didn't finish there — he drifted away from the school's bebop-era curriculum toward the city's less structured downtown scene — and instead earned his degree from Mannes College in 1996.

That downtown connection became the backbone of his career for the next decade. He formed the Ori Kaplan Trio Plus with bassist Tom Abbs and multi-instrumentalist Geoff Mann around 1996, expanding to a quartet with trombonist Steve Swell in 1997; their two CIMP Records albums, Realms (1999) and Delirium (2001), are both catalogued by Discogs as Free Jazz, and a review of Delirium in One Final Note called Kaplan "a quickly rising star among the NY ecstatic jazz cognoscenti," playing "Ornette-via-Zorn inspired freebop." In 1997 he joined bassist William Parker's Little Huey Creative Music Orchestra, a foundational New York free-jazz big band, appearing on three of its albums between 2000 and 2003 — Mayor of Punkville, Raincoat in the River, and Spontaneous. In the same period he recorded with fellow Israeli free-jazz saxophonist Assif Tsahar (Embracing the Void, with Tsahar's Zoanthropic Orchestra, and Cries of Disillusion, both 2001), with pianist Daniel Sarid (Pearls of Peril, 2001), and appeared on a 24-piece Alan Silva & the Sound Visions Orchestra recording taped live at the 1999 Vision Festival, the flagship annual showcase for New York's free-jazz and improvised-music community. The Jerome Foundation recognized him with its Award for Young Jazz Composers in 2001.

Kaplan folded his own Israeli-inflected ensembles — the Ori Kaplan Percussion Ensemble (with drummer/percussionist Susie Ibarra, Mann, and pianist Andrew Bemkey) and the Ori Kaplan Shaat'Nez Band — into that same jazz-scene period; the Shaat'Nez Band's Le Magus (2002, Knitting Factory Records) is Discogs-styled "Gypsy Jazz" and features Balkan Beat Box's future co-founder Tamir Muskat on drums and Gogol Bordello frontman Eugene Hütz as a guest vocalist, well before either group existed. A reviewer at All About Jazz described the record as sitting between his "jazz-leaning" earlier discs and the cabaret sound he'd go on to make with Gogol Bordello — a fair summary of the pivot Kaplan was already living through. He joined the rock band Firewater in 1998, toured with Gogol Bordello from 2001 to 2004, and in 2004 formed Balkan Beat Box with Muskat, the project that brought him his widest international audience and led, later, to production and session work far outside jazz (saxophone on Jason Derulo's "Talk Dirty," co-production on two Fifth Harmony albums, and a songwriting/production credit on the DreamWorks film Home).

Kaplan's jazz identity resurfaced directly in 2026 with Reverie, his first full-length collaboration with engineer and multi-instrumentalist Lihu Melamed, who first worked with Kaplan engineering Balkan Beat Box's sixth album. Released on Batov Records, Discogs genre-tags the record "Jazz" with the style "Modal," and the label describes it as drifting between modal jazz, cinematic scores, and psychedelic rock — a return, in spirit, to the genre-blending, jazz-rooted instincts that were there from the start.

Kaplan's earliest and most enduring musical identity is downtown-New York free jazz: structured compositional frameworks pushed open by improvisation, in the lineage a Delirium review pinned as "Ornette-via-Zorn." His years inside William Parker's Little Huey Creative Music Orchestra and alongside Assif Tsahar put him in direct, working contact with the same free-improvisation circle this project has already documented through Tsahar's own profile. Running alongside that is a second, equally consistent thread — folding Israeli, Sephardic, and Mediterranean folk material and rhythm directly into jazz ensembles of his own design (the Percussion Ensemble, the Shaat'Nez Band), the same instinct that later made him a natural fit for Balkan Beat Box's fusion, and that resurfaced on 2026's modal-jazz-facing Reverie.