Phaedra/Total Immersion, Barbican Hall, London<br/>Daniel Hope and Friends, Elgar Room, London<br/>From Popstar to Operastar, ITV 1

At 83, Hans Werner Henze is the grand old man of contemporary music: a Darmstadt rebel who made his home in the country of bel canto.

A born contrarian, his music embraces indignation, humour and passion. "Better a communist in a Rolls Royce than a fascist in a tank", he once said. Yet since his two-month coma in 2005 and the death of his partner, Fausto Moroni, in 2007, Henze's focus is less on the rough and tumble of political ideology than on the pale margin between life and death and the inconsolable sorrow of those separated by it.

Epilogue to the BBC Symphony Orchestra's Total Immersion day and opening event of the Barbican's Present Voices, Phaedra is the clearest illustration of the composer's before and after. Act I of the opera, completed before Henze's coma, is tautly scored for solo strings, piano, celesta, a seductive battery of percussion, caustic brass and aromatic woodwind (Ensemble Modern). The distinctive voices of Hippolytus (John Mark Ainsley), Phaedra (Maria Riccarda Wesseling), Aphrodite (Marlis Petersen) and Artemis (Axel Köhler) form a consort, high, bright and fluid. In the music, we hear the jut of Phaedra's hips, the cool revulsion of her step-son, and the Minotaur's eager stamp. Falsely accused of rape, broken on the wheels of his chariot and gored by the bull, Hippolytus dies.

Written after Henze's recovery, Act II is a fitful blur of despair, powerlessness, invasive medical procedures ("knife, screw, tube") and loss of identity. "Who am I?" sings Hippolytus, rebuilt as Artemis's plaything, blasted by blowsy trumpets, renamed Virbius, buffeted by an earthquake – Francesco Antonioni's powerful electronic bruitage – and reborn as King of the Forest in an ecstatic transfiguration. Though impeccably played and sung under Michael Boder, Henze's loss of vitality and confidence is painfully evident, while Christian Lehnert's libretto descends into obscurantism.

The contrast between Phaedra and Voices, Henze's vibrant 1973 song-cycle of protest and revolution, performed with élan by the Guildhall New Music Ensemble, was poignant. So too was Huw Watkins's survey of his music for solo piano: the defiant lyricism of Variations, Opus 13 (1948), the scherzoid whimsy of Cherubino (1981), the Bill Evans-meets-brutalism tempest of Toccata Mistica (1994) and Martin Ketz's transcription of Scorribanda Sinfonica (2003). A hard string tone gave a sour edge to Fraternité (1999) – an unusually generalised slice of pellucid harmonies and angular melodies – while Oliver Knussen's reading of Symphony No 4 (1955) was oddly diffident. Elogium Musicum (2008) is a secular requiem in memory of Moroni. Its opening movement, Accipiter, is pure and refined in its depiction of the falcons that represent the composer and his lover; Nox, violent in the rawness of loss; Cicadae, sweetly naïve in a pastoral interlude; and Adagio, elegant in mournful melodies for saxophone and cor anglais.

Formerly a venue for corporate canapes, the Royal Albert Hall's Elgar Room has been gussied up as a new, informal performance space, for which read, no chairs. The opening concert from Daniel Hope and Friends – harpsichordist Kristian Bezuidenhout, violinist Daniel Deuter, cellist Stephen Schultz, baroque guitarist Simon Martyn-Ellis and percussionist Michael Metzler – was a jolly affair in which any clashes between Hope's equal temperament and Deuter's meantone tuning were sweetened by their energy and enthusiasm. This was baroque music as fast food, a greedy feast of dances, divisions and novelties from Falconieri, Westhoff, Matteis and Vivaldi, while Metzler did things to a tambourine that I blush to remember.

As a big fan of the BBC's Maestro, I hadn't envisaged quite how bad ITV's From Popstar to Operastar would be. The show's resident critics are a rock star and a decorator; its mentors a mezzo who has yet to to make her debut in a professional production and a tenor whose vocal problems have led to a swathe of cancellations. The best musical moments came from Bernie Nolan. Dramatically, they were found in the weight-lifter knots that formed in Marcella Detroit's throat during "Casta diva" and in Meatloaf's bizarre panegyrics, delivered from a mock-up of the royal box at Covent Garden. A more instructive proposition for the opera-curious might be "From Crossover to Credibility", in which Katherine Jenkins auditions for English Touring Opera, learns one role while covering another, and works for Equity minimum on an eight-week national tour. Don't hold your breath.

Next week:

Bright young thing Luke Bedford is the Wigmore Hall's first composer- in-residence. Anna Picard attends the premiere of his new work for Birmingham Contemporary Music Group, Good Dream She Has.