• 1950s

    member of various jazz groups, one of the first promoters of modern jazz (cool jazz, West Coast jazz)

  • 1956 – 1957

    Karol Ondreička Quintet

  • 1960s

    leader of Combo 4

  • 1970s

    member of Ladislav Gerhardt Quartet

  • 1974 – 1976

    awarded by prizes of Czechoslovak Radio in Bratislava for arranging

  • 1980s

    cooperation with: Bernt Rosengren (SE), Hans Sachs (DE), Hans Koller (AT), Leo Harper (US), Kenny Wheeler (US), Charlie Mariano (US), Wolfgang Lackerschmid (DE), Harry Beckman (DE) and others.; performing in musicals: Cole Porter: Kiss Me, Kate (1978 – 1979), Vincent Yomans: No, No Nanette (1980 – 1981), N. Coward, H. Kurnitz: Ein Mädchen zum Souper (1983 – 1984), Bertold Brecht, Kurt Weil: Die Dreigroschenoper (1985 – 1986)

  • 1982 – 1983

    Karol Ondreička Trio

  • since 1990

    performing with Ladislav Gerhardt Quartet in Freie Bühne Theater in Vienna

  • 1991, 1993

    occasional concerts with Traditional Club

  • since 1991

    arranging and composing for Austrian singer and cabaretiér Topsy Küppers (tour in Poland – 1992, Bucharest, RO – 1996, Moscow, RU – 1998)

  • since 1993

    leader of Karel Ondreička Quartet / Trio

  • 1994

    cooperation with: Dušan Húščava Quintet, Jozef “Dodo” Šošoka, Gabo Jonáš, Juraj Kalász, Juraj Henter and others

  • 1996

    member of Karol Ondreička & Stano Počaji Band (Anton Jaro / Peter Oberländer, cb; Juraj Gergely, dr)

  • 1997

    recording of film music Tábor plný žien (Camp Full Of Women; author Rudolf Geri); realization of autobiographical movie Človek uprostred (The Man In The Middle)

compositions: Tmavé okno (Dark Window, 1962) • Reflexie (Reflections,1962) • Letná atmosféra (Summer Atmosphere, 1968) • Tumulus (1972) • Asawari (1975) •  Z našich hôr (From Our Mountains, 5-parts suite, 1979) • Hotel (1982) • Letisko (Airport, 1984) • Kolesá (Wheels, 1994) • Let na Vogon (Flight To Vogon, 1994) • Hommage à Barney Kessel (1994)
film music: Chlapec ako každý iný (Boy Like Any Other, 1976) • Naftári (Oilmen, 1976) • Tvorcovia lesa (Forest Makers, 1977) • Homo Faber (1978) • Matematická úloha (Mathematical Task, 1978) • Poškolák (1979) • Aj sem príde voda (Even Here Water Will Come, 1980) • Tatrasklo (1982) • Prírodné rezervácie (Nature Reserves, 1984) • Oco, mama a ja (Dad, Mom And Me, 8-part TV series, 1979) • Muzikálny zajac (Musical Rabbit, musical, 1974

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