Prom 24, Royal Albert Hall, London<br></br>Prom 25, Royal Albert Hall, London

A Dame takes her leave in perfect style

The rumours had been circulating for several weeks before but only on 31 July did Dame Anne Evans announce that her performance as the Marschallin in Tuesday's all-Strauss Prom was to be her last. In other hands the parallel narratives in Prom 24's carefully chosen extracts from Der Rosenkavalier might have felt laboured. (As the Marschallin regretfully retires from erotic intrigue, passing her lover to a younger woman, so too does Evans retire from a 35-year career as Brünnhilde, Isolde, Leonora and, of course, the Marschallin; a role that Tuesday's Sophie (Rebecca Evans) is now rumoured to be considering.) In no other hands could the - largely silent - conclusion of Act III have been quite so touching.

Those sopranos close behind Evans in age should take note. She could have gone out to a succession of Liebestods and lollipops. Instead she chose material that underlined the collaborative nature of great performance - Tuesday's relationship between singer, orchestra (the BBC Symphony Orchestra) and conductor (Sir Charles Mackerras) was exceptionally close - and the value of hearing great arias in their proper context; sharing the stage with Katarina Karneus's glorious, ardent Octavian and Rebecca Evans's exuberant Sophie. Though Mackerras's abridgement cut the burlesque of Baron Ochs and the tedious comedy of Faninal's social climbing to concentrate on the Marschallin's private journey (by far the best music in the opera), less elegant artists than Evans would be unlikely to choose such self-effacing repertoire for their last performance, and certainly not material where the next generation has the final word in Strauss's last ravishing duet. As an example of dignified leave-taking this was unparalleled; perfectly timed, graciously executed, generous to her fellow performers, elegant, subtle and illuminating. Dame Anne could, of course, continue singing. She could take the character roles; the shrews, the servants, the step-mothers. Instead she has left - like the Marschallin - while still too beautiful of voice to be cast in opera's caricatures of post-menopausal femininity. She has left while still in control, while still blessed with that steel-tempered, heroic girlishness of tone that makes her singing of the Marschallin's line "Kann mich auch an ein Mädel erinnern" ring with an authenticity singers 20 years her junior are unable to convey. She has left with diction, dignity and musical integrity intact.

After a second half like that, it seems churlish to complain about the preceding pieces in Prom 24; two of Strauss's least compelling musical responses to Greek Mythology. So be it. As an exercise in rigorous completism, this half of the concert had some merit. As an example of considerate programme planning - by which I mean introducing an audience to some wonderful rarity as opposed to beating them over the head with mediocre musical footnotes from a composer's fallow years - it had none. Worse still, only one piece was actually composed by Strauss himself; the Symphonic Fragment from Die Liebe der Danae being Clemens Krauss's 1952 over-stuffed ten-minute synopsis of the original two and a half hour opera.

Not being in any way a Strauss fanatic, I was probably less appalled by either of these than some at the Albert Hall. That said, condensing the main themes of a late-period Strauss opera while consistently retaining the bulk of an orchestral sound designed to appear only at major climaxes, as Krauss did, makes for a gruelling aural experience; one that I doubt Strauss at his most muddle-headed moments would have countenanced and one that does little to support his modest analysis of himself as "a first-rate second-rate composer." Despite a reading from Mackerras that attempted to locate some moments of clarity, one could only wonder that a composer so adept at suggesting gold, the colour, through the airiest, most delicate of orchestrations in his youth - viz the muslin-filtered morning sun of the opening of Der Rosenkavalier - should make gold, the metal, so blunt and over-literal in old age. If Strauss's horn-heavy, broad-beamed, porky-shouldered depiction of Midas seems ersatz in the context of the opera, taken out of context it resembles nothing more than a lamé wrestler's belt of the kind favoured by Big Daddy; not a good look for the BBCSO.

At least the Symphonic Fragment was assembled with some idea of instrumental range and technique. Which is more than could be said for An den Baum Daphne; Strauss's quite unnecessary 1943 a cappella epilogue to his 1938 opera and an extension of the rhapsodic art-nouveau woodwind figures that illustrate the nymph's metamorphosis. The next time anyone argues that baroque composers treated voices like instruments, which they didn't, I shall point them to this; a piece so hideously taxing in pitch and phrase-length as to be near-unsingable, unless by a consort of solo voices sufficiently supple to sustain a Strauss aria to legato perfection - the Vilar Young Artists, perhaps? - or a choir young enough to be unmindful of the vocal trauma resulting from repeatedly "floating" top As and Bs while attempting to blend with six others on the same line. Ill-translated for mature choral voices, vague in construction, bizarrely reminiscent of Marian veneration in its twee use of boy trebles (the choristers of King's College, Cambridge), and culminating in a cadence fit for a Bruckner motet, this was a stinker of a piece; conducted with little warmth or sympathy by Stephen Cleobury. Excruciating as it was to listen to - and I do mean excruciating - the BBC Singers themselves must have found it a good deal worse an experience.

So from a composer who spent a very long time on a downward trajectory - hey, Elektra was a good start - to one who seems to have recently found a way to express her thoughts concisely, effectively and vigorously; Sally Beamish. I'd written Beamish off as a pious, over-promoted waffler after hearing the premiere of her dire eco-cantata Knotgrass Elegy at the Proms 2001 but something in her Mary Shelley opera Monster (2002) made me think again. Where Knotgrass stumbled under the magnitude of its construction and the utter insubstantiality of its lyrics, Monster had - fleetingly - an energy and intelligence that seemed desperate to be realised and sustained. In Beamish's Trumpet Concerto, commissioned for soloist Haken Hardenberger and premiered at Wednesday night's Prom by Martin Brabbins and the National Youth Orchestra of Scotland, that energy and intelligence emerged again; stronger, clearer, more distinctively, wittily and confidently than I could have predicted. More impressively yet, Beamish managed this giant leap with a score so defiantly retro-stylised and movie-slick that only her quirks and bristles and odd modernist devices lift it above Fifties pastiche. Excellently played by Hardenberger and the NYOS, Beamish's concerto - her first on an urban subject and apparently inspired by Italo Calvino's Invisible Cities - quotes liberally from jazz; Clifford Brown and Miles Davis being only the most obvious sources. Yet this is clearly not Fifties music. The dimensions are subtly altered, the sidewalk dizzyingly steep, the sky-scrapers careening at Pisa-angles, the mechanical sounds - derived from a scavenging trip to a scrap-metal dealer - cartoon-like in their exaggerated weight and impact, the voice clearly that of Beamish herself. Sally in Wonderland, perhaps? Or just the kind of metropolitan kick a country-dwelling composer might need to cut the cow-pat and release some mannerist daring? Who knows? For the first time, I find myself looking forward to the next Beamish premiere.

a.picard@independent.co.uk