These are all live performances of material Baker recorded in the studio (twice in the case of Les Nuits d’Eté, so one might wonder if they are really essential listening.

Well, though Baker was a superb recording artist, who never really made a bad record, she was also a great communicator and collaborator and these performances, all with different conductors from the studio ones, bring with them the added frisson that comes with a live event, and the sound, though not as clear as in her studio performances, is more than acceptable.

It starts with a 1975 performance of Chausson’s almost Wagnerian Poème del’amour et de la mer, which she recorded two years later under André Previn. This one has, somehwat suprisingly you might think, Evgeni Svetlanov at the helm, who takes great care over dynamics and shapes the work beautifully. Baker’s range of expression, her concenration, her breath control and command of the long line are exemplary, filling its pages with rapt expression. A marvelous performance.

Baker’s recording of Les Nuits d’Eté with Barbirolli, recorded in 1967 is justly famous and has hardly been out of the catalogue. She recorded it again under Richard Hickox in 1990, but by this time her voice was beginning to show signs of wear (more noticeable in a recording than when I heard them perform the work together in concert at around the same time) and the second recording has never enjoyed the acclaim of the first. This performance under Giulini was taped at the Royal Festival Hall a month after the Chausson and it is good to hear how Baker’s interpretation changed depending on whom she was singing with. Giulini’s speeds are expansive (Le spectre de la rose at 8’29” must be one of the slowest on disc) and would tax most singers beyond their limits, but here they never flag and Baker luxuriates in the extra room she is given to make her interpretive points. As in the Chausson, her breath control is astonishing and the range of expression wide. My notes are peppered with words like searing, delicate, passionate abandon, yearning. Though it doesn’t entirely supplant the Barbirolli in my affections, it is nonetheless a performance I would never want to be without.

The earliest performance here is a 1963 recording of the Song of the Wood Dove from Schoenberg’s Gurrelieder, a work she recorded five years later under Janos Ferencsik. Baker was not yet 30 when she gave this performance and, superbly supported by Norman Del Mar, her singing is urgently free and impassioned, even better than that on the Ferencsik.

Essential listening then? Absolutely and unequivocally, yes.