The next release in this particular series of Steve Roach recordings counts as one of his most ambitious -- not only is it the third volume, but it's a three-disc effort, with each composition running nearly the length of a CD, for a total of almost four hours of music. In keeping with the title of the series, this is electronic music to sink into in a manner as chosen by the listener; Roach's own site indicates it can function as background music for other activities, along the lines of Erik Satie's "furniture music" and all that followed from it. Certainly all three discs -- individually titled "First Light," "Sleep Chamber," and "Still" -- strike a fine balance between inviting active listening and mood-setting in excelsis. Roach eschews percussion or overt rhythm of any sort in favor of open-ended, rising and falling ghosts of electronic sound, lighter tones anchored down slightly with a darker but not grim sense of deep echo and the sense of vast depths. While not per se a unique approach either in Roach's own work or in the field of ambient electronic composition in general, Roach's focus here in making such lengthy works that can and do function as involving listening -- one can step into and slip out of the drift of the music very easily, just as easily as considering it environmental white noise -- gives Immersion: Three its best quality.