A restrained and patient exploration of sine tones and white noise, Eta brings the Mengen series of sound sculptor Asmus Tietchens to a fitting close. The framework within which Tietchens is working has an inherited formality, yet he opens it up with a sense of flexible, if somewhat a-human, energy in the interplay and overlap of ambient tones and jittery sound effects. As a result, this is as much a ghostly data collage as it is a pseudo-scientific grid.

Tietchens has traversed similar territory before, a fact that he at times turns to his advantage, making continual shifts in alignment and emphasis and otherwise testing the capabilities of his resources. He gives "Teilmenge 47" a good exercise - the piece is little else but flux, fidget, and overlay; and the muted hum and jagged choir of crisp effects are highly attractive in their tonicity and elegant, glassy clarity.

Tietchens later forgoes purging his sound data of all grime before they sink into the soul, crosshatching these shafts of calm until they become detonations of blooming, messy, unbound texture. In these moments, pieces reach a nervous prostration, and take on an almost graphic intensity. Ergo, Eta-Menge is able to occasionally transcend its own trappings.