Brand-new youth operas tend to fall into two types. One is hugely rewarding for the participants, a skill learned and a treasurable group experience to be remembered for the rest of their lives, as well as for their friends and family in the audience. The other, a rarer breed, does all that but also takes a gripping subject transformed by that strange alchemy of operatic setting, stunningly well performed by singers and players alike, and sears everyone who sees it with its special intensity. Nothing fits the latter bill like no other work of its kind I've seen.

Relatively recent tweaks to the abundant London concert scene have resulted in top-end events right up to Christmas. We have in part to thank the seasonal festival at St John’s Smith Square, postponing the Orchestra of the Age of Enlightenment’s holidays, putting them together with superb soloists and choirs, and serving up major Handel and Bach. One snag: their Christmas Oratorio when I last went to hear it turned out to be only four cantatas out of the sequence of six.

Is it possible for a carol concert to have a cult following? Ex Cathedra's annual Christmas Music by Candlelight performances in St Paul’s Church have quietly grown into a Birmingham institution. The audience has evolved its own rituals: camping out through the long interval in the box pews, and sharing improvised picnics of mulled wine and mince pies.

It’s boasting, but surely true, to claim that London offers the biggest number of classy Christmas concerts in the world. How could it be otherwise with established seasonal festivals based around Spitalfields, St John’s Smith Square and the over-restored but still amazing Temple Church whose founder Knights Templar bring Dan Brown fans in droves and an inevitable daily admission fee of a fiver?

It’s nearly 10 years since Gareth Malone’s series The Choir first brought amateur choral singing to an improbably appreciative television audience. Like baking, amateur choral singing is quintessentially British – most other cultures leave them to professionals – and their affectionate place in the national psyche has created successful viewing brands.

Even if you never saw him conduct, you may well have sung one of Sir David Willcocks's carol arrangements. I remember the unnatural excitement in our church choir when the orange-jacketed Carols for Choirs 2 arrived on the scene, enhancing our repertoire with some especially juicy settings. Sir David Willcocks, who died on Thursday at the grand old age of 95, was steeped in the British choral tradition; for many, he was its heart and soul.

It’s a sunny afternoon at altitude – 1,082 metres, to be precise – in the precincts of France’s highest historic building, the austerely impressive early Gothic Abbey-Church of St-Robert, La Chaise-Dieu.

You can see the logic to the programming of this year’s Free Prom: famous opener with a good tune (Saint-Saëns’s Danse Macabre) to help wash down the new commission (Guy Barker, The Lanterne of Light), before we all get down to business with a nice choral shout (Carmina Burana). If that sounds cynical it’s really not intended to – getting this annual gift of an event right is crucial to the future of the festival itself, reaching out to the classical undecideds and getting them in to make up their own minds.

A concert of Brahms chamber music I could understand, especially given a balance between early and late. An evening of orchestral Brahms, with or without voices, needs much more special pleading. It didn’t get nearly enough last night. An expanded Orchestra of the Age of Enlightenment, including nine very vigorous double basses – where did the extra players come from?

Praise be to Carl Nielsen. Praise always, of course, to one of the greatest symphonists, and happy 150^th birthday (again), but gratitude on this occasion is due to a programme mostly lining up Nielsen works rare and familiar, for getting me to the Albert Hall to witness a surely unsurpassable performance of the Brahms Violin Concerto.