Amazingly, it’s been over a decade since the last full-length release from Belgian improvisational group R.O.T., whose public and internet presence is as elusive and obscure as the music they create. Klein Eiland is an album heavily indebted to location; all ten pieces contained on the CD were recorded in a now-demolished Brussels building of the same name, and the quartet’s abstract textural interactions reverberate through its spacious rooms and halls before disappearing into the dark, spectral void that lurks just beneath our perception. Improvised music and documentation have always been locked in a knotty, even contradictory relationship; purists insist that the identity of an improvisation is hinged inextricably on its taking place in real time, and that recording it creates something entirely distinct. These issues are complicated even further on Klein Eiland—not only was the location where it was recorded demolished, but something entirely new now stands in its place (an apartment complex which is pictured on the back of the CD sleeve). But the skilled sound artists who perform as R.O.T. have somehow managed to evoke that profound reality of impermanence even in this timeless document: the ghostly electronic transmissions, sparse concrete interplay, and distant instruments are somber, elegiac, fleeting, breathtaking in how they fill these mysterious spaces yet dissipate just as quickly. I’m reminded of similarly environment-dependent improvisations like the Battus/Gauguet/La Casa Chantier series or Akio Suzuki and Aki Onda’s KE I TE KI, but Klein Eiland is singularly sublime and harrowing, and evokes something that’s at once material and completely intangible.