Until their tentative return to concert stages earlier this year, Scritti Politti had not performed live for 26 years. Laid low by stage fright and panic attacks, the songwriter and band founder Green Gartside retreated to the studio in 1980, although he has continued to write and produce critically acclaimed albums since then.

But Gartside, who was born Paul Julian Strohmeyer 51 years ago, seemed relaxed at the first date of Scritti Politti’s low-key comeback tour in Brighton. Lean, bearded and smartly dressed in shirt and tie, the singer played guitar with a quartet of new recruits. Although he is responsible for every note on his latest album, White Bread, Black Beer, even a single-minded perfectionist such as Gartside needs collaborators for live shows.

Tunes from the band’s early years as highly politicised post-punk intellectuals were rapturously received. The best known was the woozy reggae-pop serenade The Sweetest Girl, which has lost none of its slinky, seductive charm. Equally impressive was Skank Bloc Bologna, the very first Scritti Politti single from 1978. A complex fusion of Marxist theory, fractured dub rhythms and avant-garde jazz, its off-kilter beauty still sounded remarkably fresh and timeless.

But nostalgia was only a secondary concern, with tracks from White Bread, Black Beer understandably dominating. There were early airings for the propulsive funk-rockers Doctor Abernathy and E Eleventh Nuts, which Gartside insisted on playing twice after botching it first time around. However, the album’s sweeter and softer moments left a deeper impression. The shimmering Road to No Regret and the luminous Petrococadollar, especially, were sublimely understated confections that showcased the singer’s rhapsodic, breathy falsetto.

Gartside came unstuck only when attempting to re-create heavily produced tracks from his synthetic soul-pop albums of the 1980s and 1990s. The singer became a rapper, somewhat apologetically, on a brace of ungainly hip-hop workouts. He then took a commendable stab at his 1984 chart smash Wood Beez (Pray like Aretha Franklin), although some of the song’s swooping contours and swooning harmonies were inevitably lost in translation.

Although they are unlikely to regain their past commercial peak, the return of Scritti Politti is good news. Crucially, for all his clumsy experiments and theoretical pretensions, Gartside still possesses one of the most unashamedly lovely voices in British rock.

For a former radical who once dismissed melody itself as an opiate for the masses, this intoxication with the simple beauty of pop remains a potent secret weapon.

Portsmouth Wedgewood Rooms tonight, London Scala tomorrow, Norwich UEA Saturday