[1] Opus 1 was recorded after the band's first reformation, in 1975, in the lineup which, beside Okrugić, featured Slobodan Orlić (a former Siluete members, bass guitar), Ljubomir Jerković (drums), and Dušan Prelević (a former Korni Grupa member, vocals).

[1] The song "Memento Mori" featured Dah frontman Zlatko Manojlović as guest vocalist.

The album was not well received by Yugoslav music critics, who expected more from the band on the basis of their live performances.

[3] In 2013, Opus 1 was reissued on both CD and vinyl by Austrian record label Atlantide.

[4] In 2015, Opus 1 album cover, designed by Dragan S. Stefanović, was ranked 22nd on the list of 100 Greatest Album Covers of Yugoslav Rock published by web magazine Balkanrock.