Cassette culture may now seem like some quaint hipster affectation but, for a generation growing up in East Germany in the years before the fall of the Berlin Wall, it was the prime medium for underground music. Fans would smuggle in recordings of new music from West Germany on tape, while avant-garde musicians in the eastern bloc’s most repressive country could circumvent state controls over vinyl pressing plants – and avoid the watchful eyes of the Stasi – by copying their own music on to cassettes and distributing them (like samizdat newsletters) to likeminded freaks. One of these freaks, Jörg Thomasius, ostensibly worked in East Berlin as a boiler mechanic and art gallery technician, but his real vocation was music. He was a member of the Zappa-ish collective Das Freie Orchester, ran a home studio called Tomato and hosted a show on pirate radio, drawing inspiration from experimental krautrock bands on the other side of the iron curtain. In the 1980s, he sneaked out three albums on cassette, and Acht Gesänge der schwarzen Hunde (Eight Songs of the Black Dog) – the latest in Bureau B’s Experimenteller Elektronik-Underground DDR series – compiles 10 tracks from these DIY releases. Thomasius, born in 1955, saw himself more as a conceptual artist, playfully flinging together stray sounds, and some of these tracks sound more like installation pieces. But, using primitive tape technology and whatever keyboards he could lay his hands on, he also made some groundbreaking electronica. Okoschadel is a glistening piece of keyboard minimalism in 6/8; Küss mich mein Liebchen is a wonderfully wonky slice of drumless techno; Dritter Komparsengesang is a pulsating tribal drum groove set against disembodied voices; Meditation is a blissful 22-minute ambient rumination. Best of all is Malcolm Makes the World Go Round II, which sounds like one of Steve Reich’s sonic collages that has mutated into an alluring piece of junkyard hip-hop. Gabriel Ferrandini is a Portuguese jazz drummer, and Hair of the Dog (Canto Discos) is a wonderfully spooky album that sees him playing very texturally: tight, discordant harmonies moving into drone-based minimalism and occasional drum freakouts. Swede Linnéa Talp focuses on the physical experience of breathing and bodily movement, rendered on Arch of Motion (Thanatosis Records) in meditative church organ drones. On Reflection (Temporary Residence) is a rather lovely and blissful album made by Los Angeles/London duo William Basinski and Janek Schaefer. Dreamy, arrhythmic but harmonically constant piano solos unfold very gradually, fed through effects pedals and overlaid with astral sound effects. Pianist Vicky Chow plays new five compositions by composer Jane Antonia Cornish on Sierra (Cantaloupe Music), which lurch from jabbering, rattling minimalism to Alice Coltrane-ish cosmic marvels.