Ratko Zjaca is considered a very gifted stylist, assumes many roles in his macrocosm of music: contemporary guitarist, composer, performer etc. Born in Croatia, Ratko in his early days was attracted by the sound of the guitar, both subversive sounds like those produced by Jimi Hendrix and from the classics like Bach and van Beethoven. He studied and graduated from Zagreb University. In his drive for the necessary knowledge and the enormous need for studies he sought his refuge in The Netherlands at the Rotterdam Conservatory famous for its studies of modern music. There he could get teachings by well-known masters. He also followed masterclasses and personal courses with Joe Pass, Jim Hall, Pat Metheny, Mike Stern, Bob Brookmayer, John Abercrombie and others. Unlike some of his colleagues Ratko is not focusing only on saxophone phraseologies, but is continuously expanding the guitar's vocabulary within today's world of music. Whilst improving his performance to create his typical own sound and style, Ratko as a gifted teacher with a loaded teaching schedule, is capable of transposing most advanced phrases and concepts into structures, suitable for every musician. He gives master classes all around the world for guitar and fretless guitar, in countries like Slovenia, the Netherlands, France, Croatia and the United States. After completing his study at the Rotterdam Conservatory, he also studied at New York University School of Music. He started to work with own group and with American trumpet veteran Benny Bailey group. Ratko participated at many international festivals and has been booked for the major club dates at the European and American scene. Ratko has constantly made major efforts to enrich his experience with appearances and recordings. He was also performing and recording with Benny Bailey, Gary Peacock, Reggie Workman, John Pattituci, Al Foster, Jimmy Cobb, Alvin Queen, Shawnn Monteiro etc. In April 2000 Ratko recorded "A Day in Manhattan" in New York with the jazz stars Reggie Workman and Al Foster. Ratko is currently composing music and working on a new world music project on which he plays baritone, sitar, fretless, soprano, electric and acoustic guitars - this will be the second part of his previous record Shades of Spirit, Fretless Guitar Project. Ratko just finished a quartet recording, Crossing The Border, in New York City with John Pattituci, Al Foster and Stan Mitrovic, with all original compisitions of all members of the quartet. Ratko endorses Godin Guitars.

Ratko Divjak ,Slovenija Poslednjih 25 godina dio je evropske i američke jazz scene (California Jazz Fest, Los Angeles, Monterey, Sacramento, Montreux, Berlin, Bolonja). Svirao je sa najznačajnijim jazz umetnicima: Boško Petrović, Duško Gojković, Stjepko Gut, Peter Ugrin, Art Farmer, Stan Getz, N.H.Oe. Pedersen, Albert Mangelsdorf, Tony Coy, Gary Burton, Sal Nistico, Ferdinand Powel, Gianni Basso, Richard Davis, Joe Passo, Dave Libman i drugima. Tri puta svirao je sa EBU Big Bandom.
Od 1975. član je Big Benda RTV Slovenije.
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