His artistic expression is defined by an innovative approach to the tuba, using it as both a bass and melodic instrument, often integrating electronics and live looping.

He regularly performs with Rudi Bučar Trio and Sounds of Slovenia and leads Big Band Cerknica as its musical director.

Having appeared on more than twenty albums, Goran displays versatility in a host of contemporary music genres (jazz, swing, latin, pop, folk, rock, improvised music, dixieland).

2019 saw the release of Planetarium, an original suite for solo tuba, electronics, and spoken word, preceded by 2016 jazz-classical-electroacoustic fusion release Pozabljena ljudstva (Forgotten Tribes).

Over his career, he has collaborated with internationally acclaimed jazz and improvising musicians, including Michael Moore, Han Bennink, Eric Boeren, Wolter Wierbos, Kaja Draksler, Boštjan Simon, and Tarek Yamani, and contributes to various Slovenian and European music projects.

As a composer, his work spans multiple disciplines, including film, theatre, and radio. Notable projects include the documentary Mesto svetlobe (City of Light), the interactive children’s show Mišja glasbena hiša, and the intermedia performance Plastični jazz.

Beyond performance and composition, Krmac is also an educator and workshop leader, developing unique approaches to group interaction through sound and improvisation. He is a Jazz Perfomance alumnus of the Prince Claus Conservatoire in the Netherlands.