This beautifully prepared recording issues the most compelling if belated of invitations to consider afresh a seminal work of the 1960s and assess how successfully it survives the circumstances of its scandalously aborted premiere. Andrew Porter was our man on the scene in Hamburg, and he filed a piece of understated reportage well worth digging out of the Gramophone archives (4/70). Porter and others had little but praise for the recording taken from the final rehearsal and quickly issued by DG, but Henze himself later reflected ruefully on its deficiencies, ‘the performers not giving their all but saving themselves for the actual performance, the conducting, singing and playing all matter-of-fact and calculated’.

It would be easy but naive to cast our own minds back wistfully to a time when a piece of new music mattered enough to attract flag-waving students and a division of riot police in their wake. Unnecessary, too, when Henze’s ‘documentary oratorio’ (one of several subtitles, both officially and informally bestowed upon it) acquires baleful congruence with the fate of refugees washing up on the shores of the Mediterranean, in a dreadful echo of the events in 1817 immortalised by Géricault, whose painting lent its title to the work of the composer and his librettist, Ernst Schnabel.

Peter Stein is an inspired piece of casting as the narrator Charon: wry, grizzled and self-directed with every syllable, informed by decades of experience directing others. The choral contributions from both adults and children are also irreproachable, and Camilla Nylund is no less radiantly secure than Edda Moser as the personification of Death who welcomes the poor souls on the raft into her embrace, one by one. In the role of Jean-Charles, the banner-waving African crew member in Géricault’s painting and the sole survivor of the raft, Peter Schöne may sing with less inflected sophistication than Fischer-Dieskau but his delivery restrains the piece from lapsing into bathos at moments such as the arioso with children chanting Dante (now in ensemble rather than a pair of solo voices as specified and recorded by Henze). The recording from Hamburg’s Elbphilharmonie may not convey the literal procession of souls across the stage as vividly as the original recording but it draws out more of Henze’s rich orchestration, electric guitar and all, and wraps the voices in a realistic concert-hall ambience.

Henze always liked to keep distinguished company, and the oratorio’s debts to the Passions of Bach have been overstated. For all its diffuse and over-saturated harmony, and its ready resort to quick and dirty dramatic gestures, the patchworked, two part design of his ‘Requiem for Che [Guevara]’ is better understood as a ‘taking back’ of Beethoven’s Ninth as first conceived by Adrian Leverkühn, the composer of Mann’s Doktor Faustus. When he put it on at the BBC Proms in 1977, Robert Ponsonby requested of Henze that he mute the shouts of ‘Ho-Chi-Minh’ which brought this ‘oratorio militare e volgare’ to its indignant conclusion and, thought Ponsonby, dated the piece. Henze recorded the change in his 1990 revision, which the scant performances since then have observed. Nevertheless, like Nono’s Intolleranza 1960 and Zimmermann’s Requiem for a Young Poet (1967 69), the power of its protest survives undimmed.