Finnish musician Esa Ruoho has been releasing experimental techno for about a decade, mainly under the name Lackluster. His real name is reserved for the more abstract, less rhythmical side of his work in electronic music. "Riversmouth", his first release on Attenuation Circuit, is a perfect example of this. There are no beats, but lots of things happening in terms of shifting shapes of granular textures, high-frequency oscillations working against seismic trembles in the lower bass regions, and then the occasional hauntological voice-like overtone structures. Full of harmonic tension, but never noisy, this release might appeal to fans of Asmus Tietchens, Alva Noto and other Mille Plateaux acts, or even Phill Niblock. Within the Attenuation Circuit catalogue, Esa Ruoho's release provides an exciting new take on the drone/ambient borderland also inhabited by EMERGE, B*tong, Sghor, Mystified, and Sustained Development.