Having taken his Diploma in double bass ( 1983 ) and Graduate in Popular Music ( 2007 ) at Pescara Conservatory of Music, has worked extensively in the field of classical music and jazz music.
He attend, for a short time, the courses of "Composition and Jazz Arrangment", with Gerardo Iacoucci, at the Frosinone’s Conservatory of Music.
In the 1982 he tooks part in Bruno Tommaso’s Seminar at Siena Jazz, and starting his musical career playing with jazz musicians from Abruzzo’s area. Than he performed with Italian and American musicians playing various kinds of music, from mainstream jazz to progressive jazz, from etno music to blues and latin. He worked with European Musicians such as Claudio Fasoli, Tino Tracanna, Marcello Tonolo, Mimmo Cafiero, Marco Di Battista, Franco Cerri, Malcom Ball, Geoff Warren, , Tom Sheret, Michele Di Toro,Tobias Ott, Rita Marcotulli, Michael Roachford, Balazs Bagiy, Arup Kanti Das, and  American  such as Badal Roy, Karl Potter,Bob Ferrazza, Phil De Greg,  James Thompson, Garrison Fewell, Tony De Caprio,   and many others, playing in Concert and Festival [ Pescara Jazz (2002- 2003-2007), Odessa Jazz Festival (UC-2001), Palermo Jazz Festival Musica Insieme (Ita.2003), Southend Jazz Festival (GB-2004), Malbourne Italian Jazz Festival (AU-2004), Szekesfehervar Jazz Festival (UH-2007 )] .
He tooks part in Radio sessions (“La Stanza della Musica-Radio 3-Italy-2003; SBS Jazz Radio- Melbourne-AU 2004-) .In ’97 was published his first CD on italian label Splasch Rec.: "SUITE & SONGS", which had excited the interest of several jazz magazine in Italy and abroad. His second cd as leader , "MINIATURES", was released on Splasch Rec label on october ’98 and a new work for MAP Records,"DUETS", with Claudio Fasoli, Garrison Fewell, Geoff Warren and Tino Tracanna ,was published on 2001.With  his Fourtet  ( Massimo Manzi, Giovanni Ceccarelli and Geoff Warren) he  recorded the CD “ DESIDERIO “ on 2003  ( Splasch Rec.). In 2009 the Italian label Drycastle Recordswill  has published Marcello Sebastiani’s first  CD on solo bass, “ BASS EXPRESS “ . In 2020 was release a CD with trumpeter Oscar Gabriel Rosati, a walking on the philosophy  way : DIALOGI & PROGRESSUS; in the 2021 Sebastiani  published is firsth poems with doublebass backgroud for Notami Label.
In the some year was release a new work in Trio :BASS LETTERS (Ed. Notami) with Massimo Manzi and Michele Di Toro.
Short Discography: 1997- SUITE & SONGS  - Splasch Rec. CDH 602.2 (as leader ), 1998 - MINIATURES - Splasch Rec.  CDH 665.2 (as leader ), 2000 - ARIA  DEL SUD  - Step Musique CDS 1022 (Alex Cavallucci ), 2001 - DUETS - MAP Rec CDM 201 (as leader ), PESSOA - Splasch Rec  CDH 752.2 (Marco Di Battista ), HUSH - ECAM Lab. CDL 1025 (Cintura Choir ), 2002 - “ TRIO“ - P. P. (Corrado Equilibrati ), 2003 -DESIDERIO - Splasch Rec  CDH 902.2 (as leader ), 2004- FRAMMENTI D’ANIMA – Ghita Records- GCD 1001-(Badal Roy TRIO- USA only), FLAYING WITH MUSIC- Music  Center BA CD 061 ( Michele Di Toro ), 2005 – LIVE SESSION – Splasch Rec. Word Ser. CDH 805.2 ( W.S.B  TRIO ), 2006- FRAMMENTI D’ANIMA – FMR Rec- (Badal Roy Trio  - EU ), 2007- AFTER POP SUITE – Stefano Taglietti Ensemble – RAI Trade, 2008- BASS EXPRESS "Solo Bass"- Drycastele ( solo bass from  various themes), 2020- DIALOGI & PROGRESSUS- Edizioni Notami-NJ032- (with Oscar Gabriel Rosati), 2021-AGOSTO -Edizioni Notami- (( Poems and Music, BASS LETTERS- (Edizione Notami)- NJ.