Sebi Tramontana, born Sebastiano Tramontana on December 12, 1960, in Rosolini, Sicily, started on guitar as a child, moved to soprano saxophone in the late 1970s, and switched to trombone in 1982. During a radio production he met trombonist Giancarlo Schiaffini, a meeting he has credited to bassist Bruno Tommaso; Schiaffini convinced him to move to Rome and study with him at the A. Casella Conservatorio in L'Aquila. Tramontana completed his studies there in 1990 and joined the Italian Instabile Orchestra the same year, the large improvising ensemble that would remain a constant in his career for the next three and a half decades.

His first solo trombone performance came in Rome in 1992, followed by solo dates in Zurich, Mulhouse, Clusone, Cologne, Ruvo di Puglia, Roccella Jonica and Gottingen. In 1994 Georg Grawe invited him to "Two Nights of Random Acoustics" in Cologne, after which Tramontana joined the Georg Graewe Quintet and toured Europe with it; the two also recorded the duo album Schz! in Munich in 1998. By the mid-1990s he had settled in Munich, Germany, where he still lives and remains an active presence in that city's improvised-music scene.

Tramontana's Discogs discography runs to 26 releases under his own name or as a named co-leader, every one of them genre-tagged Jazz, spanning Splasc(H) Records, Leo Records, Wobbly Rail, Rudi Records, Palomar Records, FMR Records, We Insist! Records and Fundacja Sluchaj!, among others. His earliest leader credit, Red & Blue (Splasc(H), 1988), is a quartet recording with Russian reedman Vladimir Chekasin, Italian alto saxophonist Mario Schiano and Soviet drummer Vladimir Tarasov, made at Rome's Wonderland Studios. His first record under his own name alone, Il Giorno del Santo (Wind, 1992), was recorded live at Rome's Controindicazioni 6 Festival.

A long sequence of duo albums forms the backbone of his catalogue: E'vero (Leo Records, 1999) with French bassist Joelle Leandre, recorded live at Munich's Lukaskirche in 1997; Chicago Defenders (Wobbly Rail, 2002) with Chicago trombonist Jeb Bishop, taped at Chicago's Experimental Sound Studio and the Velvet Lounge in July 2001; 15 Instant Songs (self-released, 2010) with German reedman Frank Gratkowski; Wind & Slap (Rudi Records, 2011) with his old teacher Giancarlo Schiaffini, the two trading trombone, euphonium and tuba; Live at Dobialab (Palomar Records, 2011) with Italian bassist Giovanni Maier, recorded in 2009 at Staranzano, Italy; Live at Spanski Borci (Leo Records, 2016), a second duo record with Gratkowski, recorded in Ljubljana; Down at the Docks (We Insist! Records, 2019) with Rome-based cellist Luca Tilli; and Han Jiae (Inexhaustible Editions, 2020) with Portuguese-German cellist Guilherme Rodrigues, recorded in Berlin.

He has also led or co-led trio and larger-group projects: The Chicken Check In Complex (Leo Records, 2002), a trio with Leandre and Portuguese violinist Carlos Zingaro recorded live in Paris; Moon Extermination (Lazzarecords, 2007), a trio with pianist Fabrizio Puglisi and Giovanni Maier, recorded live in Bologna in 2006; Night People (Palomar Records, 2010), a sextet with writer John Corbett, Terri Kapsalis, cellist Fred Lonberg-Holm, bassist Kent Kessler and clarinetist Guillermo Gregorio, recorded in Chicago; Hell Dunkel (FMR Records, 2017) and SoundEnergyTransformation (FMR Records, 2018), both with Munich reedman Udo Schindler; Canto Senza Parole: Recitativo (Arch-Musik, 2023) and Canto Senza Parole (Allegria) (FMR Records, 2023), a trio with Schindler and drummer Eric Zwang Eriksson; Frush (FMR Records, 2024), with Dutch saxophonist Luc Houtkamp, British pianist Steve Beresford and drummer Martin Blume, recorded live at Cologne's Loft; Flying Slippers (We Insist! Records, 2025), a trio reuniting him with Tilli and adding Beresford; and Almost This (Fundacja Sluchaj!, 2026), a trio with Gratkowski and Beresford, recorded at the Loft in Cologne. His own solo record Unfolding to Be You (We Insist! Records, 2022) sets fifteen pieces for trombone, voice and extended technique, including a text in Spanish.

Running alongside his own projects is three and a half decades inside the Italian Instabile Orchestra, the large improvising ensemble co-founded in 1990 by musicians including Giorgio Gaslini, whose large-scale work Masks (Soul Note, 1992) Tramontana recorded on trombone and euphonium alongside fellow orchestra members Giancarlo Schiaffini, Guido Mazzon, Pino Minafra, Mario Schiano, Bruno Tommaso and others. The orchestra's own discography, on which he appears throughout, includes Skies of Europe (ECM, 1994), Litania Sibilante (Enja, 2000) and The Owner of the River Bank (Enja/Justin Time, 2003), a large-scale meeting with American pianist Cecil Taylor recorded with the full orchestra. In 2007 the orchestra's personnel, Tramontana included, also recorded Creative Orchestra (Bolzano) 2007 (Rai Trade, 2008) under the direction of Anthony Braxton. He has likewise recorded repeatedly with trumpeter Pino Minafra's own large-ensemble projects, MinAfric (Sud Music, 2015) and For Mandela (Sud Music, 2017), the latter featuring South African drummer Louis Moholo and British pianist Keith Tippett.

Tramontana's playing is built around extended trombone technique: multiphonics, vocalization through the instrument, mutes and objects used to modify its sound, and a body-and-voice approach to the horn that AllMusic's biography describes as melding the instrument with his own vocal cords. For more than thirty years he has also performed unaccompanied, solo pieces ranging from thirty seconds to over eight minutes, a format documented most fully on Unfolding to Be You.

Tramontana works almost entirely inside European free improvisation, a tradition with no fixed repertoire and little conventional harmony, built instead from real-time interaction between players. His discography favors small, unfixed groupings: duos with a single reed, string or brass partner (Gratkowski, Leandre, Bishop, Rodrigues, Tilli, Schiaffini) recur far more often than any standing working band, and even his larger projects (The Chicken Check In Complex, Night People, Frush, Almost This) are one-off meetings of several improvisers rather than a repertory group. This mirrors the duo-centred catalogues of several other European free improvisers active in the same scene, and situates him closer to the Instant Composers Pool / Free Music Production generation of musicians (several of whom, like Gratkowski and Beresford, are his direct and repeated collaborators) than to any school built around written composition.

His central technical signature is the integration of voice and trombone: playing and singing or vocalizing simultaneously through the horn, multiphonics, and the use of mutes and small objects to extend the instrument's timbral range well past its conventional jazz vocabulary. This is documented across his solo output and credited explicitly in multiple reviews of Unfolding to Be You, which AllAboutJazz described as melding trombone with voice "to create notes" and "breathy sounds" through the mouthpiece.

His long tenure in the Italian Instabile Orchestra, a large improvising ensemble rather than a conventionally arranged big band, also shaped his vocabulary: playing trombone inside a sizeable, largely improvised orchestral texture, alongside other trombonists including his teacher Giancarlo Schiaffini, has run in parallel with his small-group work for his entire career rather than being a separate chapter of it.