Tape's fourth album finds the Swedish trio working once more on their own, having experimented successfully with Marcus Schmickler on 2005's Milieu. Luminarium is both an extension of that album's extremely careful blend of acoustics and electronics -- the lines between the two are so finely drawn as to be nonexistent -- and a softer contemplation of sound. There's something present, just, which calls to mind the most graceful moments of Robert Wyatt or late Talk Talk, but without the overtly anthemic drive of those acts -- a sense of jazz as spacious exploration, of texture and fragmentation within a careful, calm context (the blend of stuttering feedback guitar and steady piano on "Dripstone" in particular sounds like something from side two of Laughing Stock, in the best possible way). The woozy but never sloppy melody on the opening "Beams" gives a sense of the band's carefully balanced aesthetic at work, with the guitar sounding almost like a soft waltz while occasional percussion fills and the soft drift of backing keyboards let the song float a little more loosely -- the rest of the album feels much the same way, where an overall feeling throughout contrasts against the realization that a listener is never quite sure where a song will go next. Consider the introduction of the descending keyboard part on "Fingers," first on its own, then slightly overdubbed, and later suddenly but quietly complemented by both a quiet guitar solo and a shuffling drum loop that increases and decreases in volume constantly. Songs such as "Mystery Mutiny" explore a more overtly free-form approach, with the electronics there very much calling late '70s space/synth explorers to mind, while the elegiac, acoustic guitar and drone keyboard flow of the penultimate song, "Illuminations," not only ties in with the album title but with the feeling of the album as a whole, a softly enveloping glow.