“Try to imagine the whole universe beginning to ring and resound” wrote Gustav Mahler of his Eighth Symphony. “There are no longer human voices, but planets and suns revolving.” It’s an image that captures the impossible scale and mind-boggling ambition of this so called “Symphony of a Thousand”.

The greatest war films are those which capture the terrifying physical and psychological ordeal that soldiers face, along with the sheer folly and waste of it all –  Paths of Glory, Come and See, Apocalypse Now, Saving Private Ryan, most recently Dunkirk. Sam Mendes’ 1917, which has just won two Golden Globes and could well triumph at the Oscars, joins their ranks.

In youth we trust. That can be the only motto worth anything for 2020, as the world goes into further meltdown. So it was startling, stunning and cathartic, two days after the big downer of 3 January - the American horror clown seemingly in competition with the Australian apocalypse - to witness 164 teenagers under a conductor they clearly adore, Jaime Martín, making their voices heard, sometimes literally, in 20th century music of fear, anxiety, protest, violence and just a smidgen of hope.

Everyone’s doing Weinberg now, or so it seems. The Polish-born composer who became a close friend of Shostakovich was born 100 years ago, and there’s plenty of his music to go round.

Half a billion dollars is what the top five most lucrative estates of deceased musicians earned last year. The figure represents the cunning work of a few people to turn “legacy” into its own immortal industry. To watch a program on this theme is to peek through the keyhole of a locked cabinet. How does the “RIP business” work? How much – so goes another question – are we really allowed to see?

This edition of Peter Culshaw’s periodic global music radio show features guest special guest Anne Pigalle. A flâneuse and doyenne of the urban demi-monde, she came to our attention recording for ZTT Records in the 1980s and ran Soho nights at the Café de Paris, did Japanese commercials for Jean-Paul Gaultier, and a series of innovative albums including Madame Sex.

Mahler’s Fifth Symphony is a repertoire piece nowadays, probably as familiar to as many listeners as to orchestral players, which means you look for something distinctive in any performance to identify its essential quality against all the others.

Every ten years or so Thomas Adès writes a piano concerto and the latest had its UK premiere last night at the Royal Festival Hall, played by Kirill Gerstein and conducted by Adès himself.

Changes from the artists originally advertised can bring some happy discoveries. Sir Mark Elder, though present in the audience to hear last night’s Hallé performance at the Bridgewater Hall, was still recovering from surgery and so did not conduct it, as he’d planned to when the season was announced. Instead, the Hallé Youth Orchestra’s music director (and noted choral director) Ellie Slorach took the baton for the first work in the programme – Weinberg’s Rhapsody on Moldavian Themes.

The Barbican’s latest offering – a look at the clubs and cabarets set up by artists mainly in the early years of the 20th century – is a brilliant theme for an exhibition.