"As a follow-up to Munster Records' previous work reissuing the recordings of Pau Riba, key figure in Catalonia's counter-culture and music scene, Munster presents Ars Erótica, one of his most sought-after singles, in the 50th anniversary of its original release. This is a mysterious and surprising record that was originally released on Concèntric and featured alternative edits of two songs previously included on his classic album Dioptria/1.

Ars Erotica (Non Est Mihi) is edited to last just under five minutes, after taking out some verses and arrangements, although keeping intact its psychedelic folk-rock essence, with plenty of fuzz guitars. On the flipside you find possibly the most interesting recording on this single, clearly showing what the vibe and work method were at the studio: all the musicians playing simultaneously in a chilled-out atmosphere.

This edit of Rosa d'Abril (L'Amor s'hi Posa) starts right at the same point where the album edit finishes, with Pau Riba backed by the band Om jamming and some of the guest friends at the studio joining in, including the film producer and script writer Joaquim Jordà, who Riba wrote this song for."