One of the highlights of last year’s Glyndebourne Festival was the revival of Richard Jones’s Falstaff, spruced up and invigorated by Mark Elder’s conducting of the Orchestra of the Age of Enlightenment and a beautifully balanced cast. Elder is also in charge again for the festival’s third new production of this year, Tom Cairns’s La traviata, although with the London Philharmonic this time. His conducting is extremely fine once more, managing to be lucid and intelligent, thrillingly dramatic and lovingly shaped. The playing of the LPO is of supremely high quality throughout, while the cast features a genuinely exciting leading couple. Venera Gimadieva and Michael Fabiano, as Violetta and Alfredo, both sing with an almost languid, big-voiced ease that’s a pleasure to witness. Her sound is creamy and penetrating, with Act I’s fireworks cleverly and convincingly negotiated; his is virile and exciting, although perhaps a little unstintingly so at times.

They both look the part, too, and when Tassis Christoyannis’s solidly sung silver-fox Germont père appears in Act II, he does so less as an alien invader to his son’s world than as a convincing member of it. More than ever, the extended duet between Germont and Violetta exists as the opera’s emotional heart, as well as its turning point: here Cairns’s direction brings out exquisitely detailed acting from Gimadieva and Christoyannis, with Elder’s conducting tracing the psychological to-ing and fro-ing with supreme musical intelligence. I can’t remember the important difference between this profoundly moving dialogue and Germont’s subsequent one-way lecturing of his son ever being so clearly delineated.

Otherwise the production — updated to an unspecific, semi-abstract and smartly dressed modern world — is often effective but largely anonymous. Hildegard Bechtler’sset features a velvet-upholstered curved wall on the right, a more austere one on the left, various minimal bits of furniture around and about, and a back wall for subtle projections (by Nina Dunn). Violetta materialises, gradually illuminated through a gauze, ahead of each scene before the rest of it appears around her. Act I opens with a tableau of formally dressed cigar smokers to the left, and a red curtain projected at the back, simultaneously bringing to mind two recent ENO Verdi productions: Christopher Alden’s gentlemans’ club Rigoletto and Peter Konwitschny’s own fiercely concentrated take on Traviata. The decision to promote Annina from mere maid to confidante — thankfully not over-emphasised here — also reminded me of Dmitri Tcherniakov’s disappointing 2013 staging at La Scala.

As it progresses, though, one waits in vain for the production to assert its own identity. Instead it’s happy to stick with a vagueness that seems increasingly to represent a mere lack of ideas. We see Violetta knock back some pills, but otherwise her illness remains largely unacknowledged, the sudden relocation to her deathbed in Act III unexplained. In the final act Gimadieva also seems to have been left to her own devices, her Violetta switching to artfully sung but relatively unmoving autopilot. Here even Elder starts to overcompensate for Cairns’s apparent loss of conviction, opting for some strange tempo choices and balancing decisions. For Violetta’s eventual demise, she is simply left alone to walk up stage and collapse. But, compared with the way she is abandoned in Konwitschny’s production — a biting indictment of the cowardly men who use and discard her — this feels toothless and merely decorative. At the interval (placed halfway through Act II) I’d been bowled over; I left underwhelmed and unconvinced at the end.

I’d become unconvinced at a much earlier stage at Opera Holland Park’s new Norma — at least with regard to Olivia Fuchs’s production. Updated to a present-day conflict zone, with invading troops at odds with mystical tree-worshipping locals (instead of the specified Romans and druids), it places all the action within a detention pen through which anyone seems to be able to come and go as they please. The clunky plot is matched by even clunkier direction; ideas remain undeveloped, inconsistencies unresolved or ignored.

Yvonne Howard is entirely unfazed by the demands of Norma, which she sings with admirable refinement and rich tone. But her priestess, in the context, is unable to muster the necessary basic grandeur, fire and charisma to carry the drama. As Adalgisa, Norma’s apprentice in druidry but rival in romance, Heather Shipp offers plenty of smooth, stylish and well-produced singing — plus, like Howard, a couple of misjudged high notes. Joseph Wolverton, as Pollione, the Roman soldier they both love, has some moments of elegant plangent tone, but is generally underpowered; not so Keel Watson’s imposing Oroveso. Peter Robinson’s conducting is lively and flexible, if a little impatient at times. The City of London Sinfonia plays with spirit; the OHP chorus sings with its customary passion. So at least Bellini’s gloriously melodic score, too rarely heard, comes across persuasively.