Best Liars moments: crawling down the cavern of bass that is ‘This Dust Makes Mud’ (the 30 minute closer to Liars’ debut), while shrooming. Being front-row on the “They were wrong…” tour, Angus yelling lyrics at everyone from inside a hood, clasping the microphone in monster gloves, and when he gets to me, I yell the next line back – he looks surprised (the album’s not yet out), but he’s approving. Getting free tickets (from Rough Trade) to the UK debut of Drum’s not Dead, on my birthday, paired with a screening of a 9/11 conspiracy theory movie; meeting Aaron and Julian halfway through and babbling at them until they give me badges.

Okay, so, I may be partisan, but the point is: Liars are the kind of band you CAN get obsessed about… after all, they ditched the sinuous bass and disco-punk sound almost as soon as they invented it; turned synths into a hardcore instrument in a way that tourmates Black Dice never could, then ditched them, too; put the drums front and centre, then pushed them back again. After a run of good luck diving into the unknown, the fourth Liars album was a little unfocused in its alternation between savage guitars, and lo-fi gothic synths; the question now is whether the fifth will show them discovering another unifying aesthetic to redeem rock.

More than ever before, the main reference point is early Sonic Youth (i.e. Confusion Is Sex, Bad Moon Rising…), when atmosphere was more important than structured songwriting (…from EVOL onwards). There were echoes of SY on previous Liars albums, but many tracks here are built around somnolent chants over soundscapes of urban decay, interspersed with angrier fragments like the heckles of street-people and punks. (They’re living in an LA ghetto now, FYI.) In places, you might glimpse what they mean by the “Sisterworld” – when Angus double-tracks his world-weary vocals he doesn’t create the instant harmonies that make it such a neat studio-trick, but instead gives the songs a sense of reluctance about saying all they mean; the tremulous second vocal acts as an unconscious, a spectral double, a pull towards another fate, in a parallel world.

Whereas the fourth album opened with a strong pair of singles (guitar- and synth-based, respectively), you have to immerse yourself in the Sisterworld, rather than expect to be dragged there. This album’s project is to rehabilitate woodwind, brass, and acoustic instruments in the context of experimental-slash-hardcore music, and on the whole it’s a success (the pianos are especially evocative, sounding like they might once have soundtracked silent films). ‘Proud Evolution’ is the best Liars track in a long while, with a strong, eerie melody hovering hawklike over the landscape of the whole song. On the other hand, several songs alternate between sparse, atmospheric sections, and sudden bursts of frantic riffing distinguished more by the effects-pedals than the notes; that’s when you realize what might have made this great, or at least “crossover” – more songs with a distinct backbone. They’ve still got that layer of Liars-brand artfulness over everything – beautiful as a close-up of rust, verdigris, moss, or mould – and they still do “cute” (ending on a track much like Drum’s own closer) but this is another good album from a great band, rather than a true landmark.