If you were new to contemporary opera, you might think it was forbidden for modern works to be funny. Tragedy is still the default setting for major commissions. You only get serious money if you have serious thoughts and serious music, it seems. At the Royal Opera, the policy is to stage unfunny, ancient buffas on the main stage and sharp, modern ones in the Linbury Studio Theatre. Gerald Barry’s The Importance of Being Earnest is the latest.

In Bergen’s Grieg Hall (one is tempted to say the Hall of the Mountain King) the 2013 Bergen Festival concludes with the mournful tolling of bells. A consonant “Amen”, like a healing benediction, is the last word and with it comes perhaps a glimmer of hope. But the mood is sombre not celebratory. Benjamin Britten’s War Requiem, for all its theatricality, would be an unlikely choice to close a festival in any year but this - Britten's hundredth anniversary.

There were a small but substantial number of children dotted around the auditorium at the opening night of The Perfect American, and one hopes they hadn’t been led to expect singalong-a-Disney, all bright colours and catchy tunes. The piece takes place in the last few months of Walt Disney’s life, as his diagnosis with late stage lung cancer prompts introspective angst about the meaning of his success and legacy, and the terrible contrast between his own mortality and the agelessness of his creations. The great man’s personal flaws are laid bare.

Three hundred years ago we danced and ate to art music. Before that we worshipped to it. In the 19^th century we began to sit and stare at it. The immersive music movement of the past decade has moved things along again. Today we are encouraged to swim through performances, sniffing the music out, hunting it down. The latest ensemble to free themselves from the sit-and-stare model are the enterprising outfit, the London Contemporary Orchestra (LCO). For their concert on Friday we had to go down 200-odd steps into the labyrinths of the disused station at Aldwych.

“A book,” says the Boy-Illuminator in George Benjamin’s latest opera Written on Skin, “needs long days of light.” He speaks for Benjamin himself, a composer who, for all his fabulous musical mind and ear, has never found composition easy and has often struggled to produce work of any kind that satisfies his own meticulous standards.

Zipangu. What a name for a piece of music. Such a strange and suggestive collection of vowels and consonants. Such a musical string of sounds. A fascinating name. The name, in fact, the programme told me, for Japan during the time of Marco Polo. The life of the composer of the work, Claude Vivier, is fascinating, too, in a grisly way. While completing an opera about a young man who stabs a stranger to death, Vivier was murdered in his Paris flat by a rent boy. Incredible story, incredible-sounding work; you can see why programmers are increasingly attracted to Vivier.

Imago, Glyndebourne’s latest Community Opera exercise, putting the cap on 25 years of pioneering educational outreach, is one of those operas where you need to read the programme synopsis first. 

It’s hard to put one’s finger on why George Benjamin’s new opera doesn’t work. It comes to Covent Garden with a wind in its sails. Its outings in Europe have all received high praise. It boasts a classy cast, Martin Crimp as librettist and Benjamin at the helm of the orchestra. The story is a captivatingly horrific medieval morality tale that often goes by the title of "the Eaten Heart story". And there’s little wrong with Katie Mitchell’s production.

Minimalism was born of popular music. The drones came from John Coltrane, the tape experiments from fiddling around with songs from the charts, the first rhythmic and melodic explorations from the folk music of Africa and Asia. And all the pioneers started their careers as jazzers (La Monte Young and Terry Jennings were saxophonists, Terry Riley a ragtime pianist, Steve Reich a drummer).

Like a piece of conceptual art, it may be the idea rather than the actual music that is the most significant thing about the world premiere last night of Steve Reich’s Radio Rewrite. There will be a hundred times more people discussing the fact that Reich has taken on Radiohead than actually listening to it. Rather than variations, it's a 16-minute piece performed by the London Sinfonietta in which elements of a couple of Radiohead songs are referred to, often obliquely. Chords are shuffled around, but snatches of melody survive.