Witch ‘n’ Monk are a theatrical Anglo-Colombian duet featuring two very different musicians. Mauricio Velasierra plays a variety of flutes, while Heidi Heidelberg is a classically trained soprano singer who plays spiky prog-punk riffs on guitar while using looper pedals. They’ve released two mini-albums as Bitch ‘n’ Monk, but their new moniker rather suits the slightly shamanic, unearthly quality of their music. This self-titled LP, recorded in rural Wales and in a former Stasi bunker in Berlin, is their first for John Zorn’s Tzadik label, and you can see what attracted a sonic anarchist such as Zorn to their music. They talk of “abandoning the egoistic 20th-century idea of the lone, male composer writing his opus” by recording stream-of-consciousness music: hours of sleep-deprived, endlessly mutating improvisations are sliced up and used as the basis for these slightly manic musical collages. Rather like Zorn, they make a mockery of genre – thrashy guitar riffs are overlaid with Amazonian panpipe melodies and flashes of Bollywood strings; multi-tracked choirs are digitally mutilated with terrifying effect; Reich-ish minimalism mutates into ecstatic samba. At points you could be forgiven for thinking that you’re listening to an opera, a futuristic hip-hop track and a folkloric field recording, all playing at once, in almost unlistenable discordance. The album features several guest percussionists: drummer Nicolas Stoker delivers twisted, junkyard funk beats for the opener Escarbando; Seb Rochford freaks out on the playful, childlike postpunk of Coal Mine; The Cage sees Gidon Carmel providing a juddering tango in the disorientating time signature of 13/8. But Witch ‘n’ Monk don’t really need a drummer – they can create hypnotic beats by looping Heidelberg’s muted guitar riffs or Velasierra’s breathy overblowing. On Outchant, the pair improvise angular riffs over a compelling rhythmic chant; on the closing track Gualchovan, they provide ghostly noises over an antique drumbox. If there’s a criticism, it’s that Heidelberg and Velasierra are rather profligate with their melodies: each track features an abundance of riffs and hooks that could provide the basis for a dozen proper songs. This is an album that frequently invokes the exploratory spirit of postpunk, but it would be fascinating to hear Witch ‘n’ Monk forced into punk’s three-minute concision. ] Last year’s debut album by the Berlin-based Polish composer Hania Rani, Esja, was a series of minimalist pieces for solo piano that were both hypnotic and slightly soporific. The ambitious follow-up Home (Gondwana Records, released 15 May) moves into Nils Frahm-ish electronica and sees Rani singing, in English, on five tracks, sounding like a young Kate Bush. But the simple solo piano numbers – the spiky, multi-tracked Buka, the Pyramid Song-inspired F Major, the childlike Rurka – provide the emotional core. French pianist Benjamin Moussay is best known as an accompanist for the multi-reedist Louis Sclavis, but Promontoire, his first solo album for ECM (released 29 May), is a series of free improvisations that often sound like perfectly plotted miniatures. The terrifyingly fast Don’t Look Down resembles Conlan Nancarrow; L’oiseau d’or and Chasseur de plumes sound like some of Bartók’s more atonal piano suites; but Moussay’s default position is Satie-esque introspection – minor-key ballads with delightfully quizzical chord changes.