This recording stems from the participation of Nuno Trocado (guitar, electronics) and Sérgio Tavares (bass, electronics) in the interdisciplinary project Expurgar, led by artist Dária Salgado, which she described as "an intimate geography, scored in and lived through a body poetically articulated with a lived-space, in a notional play against the fear of death". With the themes, contexts, memories and pre-existing materials of the project as a starting point, Nuno and Sérgio went into the studio to improvise, expand, and develop them further. The result is this series of "sonic derivations".