On Katelyn Clark and Mitch Renaud's Ouroboros astronomical and astrological phenomena, concepts and symbols such as the Great Year or the Eternal Return serve as the starting points for sonic explorations and experimentations. Focusing on a uniquely tempered range of frequencies, from low-end drone rumbles to airy pipe swirls, the duo develops a minimalist and highly evocative sonic universe on their debut album for Hallow Ground. Working as composers, improvisers and curators in Canada's vibrant experimental and early music scenes, Clark and Renaud began developing Ouroboros through extensive improvisation with a reduced setup. Clark, who has worked extensively with historical keyboards since her studies in Amsterdam and Siena, played a small pipe organ modelled after a 14th-century instrument while Renaud brought a modular synthesizer and his interest in feedback systems to the collaboration. Later, the duo further refined their artistic dialog and the sonic interactions of the two instruments through the shared space of a two-day recording session in Vancouver. Subtle crackling, acoustic beating and other (psycho-)acoustic effects in five pieces document this encounter, giving the music a profound physicality while hinting at the bodily presence of the two collaborators. Just as the cyclicality of natural phenomena or the repetition of planetary movements is both a scientific fact and of the cultural imaginary, the sound worlds of Ouroboros are fundamentally rooted in time and space while transgressing the idea of a "here and now" through their conceptual links to geological and planetary time. The interplay of portative organ and modular synthesizer, which merge fluidly and in ever-changing ways, leads to a kind of circularity, a timelessness, a no-time. At the same time, the movements and subtle changes undermine the idea of repetition in the negative sense. After all, the Eternal Return, as Gilles Deleuze writes in regard to Nietzsche, is not the return of the same but a repetition of repetition. The only constant is change, the production of new intensities, of new forms of life -- and of new frequencies.