John Cage, the focus of an adventurous three-day mini-festival in Bristol, is possibly one of the most influential figures in 20th-century culture. As much a practical philosopher as a composer of note, he made artists, writers and musicians think about the nature of chance, our place in nature and the role of the subject in the creative process.

Concerts are not what they used to be: in an attempt to break the mould of conventional performance styles, promoters and artists are increasingly turning to explanatory introductions, visual aids and other means of drawing the audience in, as if music alone could not work the crowd. The Senegalese singing star Baaba Maal is touring with the journalist and playwright Kwame Kwei-Armah, and their show combines relaxed but clearly scripted conversation with stunning songs from Maal’s Fulani repertoire.

Theatre, particularly tragedy, can pack a terrific punch when things are kept simple – even if the themes evoked are enfolded in layer upon layer of complexity. Brian Friel’s Faith Healer, a play with three characters, each of whom takes to the stage alone, explores in a multifaceted way the life of an itinerant Irish healer who plies his trade along the backroads of the Celtic fringes of Britain.

An “Army of Generals” suggests a kind of supergroup, a fighting force made up of leaders rather than followers. If Charles Hazlewood’s band, which has just started a residency at Bristol’s St George's, is such a host, then he presumably is the Generalissimo, primus inter pares, whose mastery is exercised with a showman's display of almost innocent ego.

Next Friday, my amazing period-instrument orchestra, Army of Generals, begins a new residency at St George’s Bristol. The aim of this unconventional and high-octane series of concerts - which will be performed by what I refer to as my crack squad of period instrumentalists - is to raise the bar for people’s engagement with music and to bring some musical protein to a city which I think is so desperately in need of it.

London is a magical place at this time of year - so many streets with their individual lighting schemes and colours, and nowhere I think is lovelier than the new-look Southbank Centre, where from the side of the Festival Hall swings a spacious canopy of silver-blue trickles reflected in the glass of the new cafés alongside, a captivating, super-chic Thames-side installation. Into this urban grotto last night Kneehigh Theatre’s bouncy, folksy Hansel and Gretel came as welcome as a homemade mince pie.

Swallows and Amazons is a quintessentially English story: a heart-warming hymn to decent values, the codes of sailing and the youthful spirit of adventure. Set in 1929, at a time when the country faced financial meltdown, it is perhaps not surprising, in our equally uncertain times, that Arthur Ransome’s feelgood Lakeland classic should have been adapted for the stage. Tom Morris’s production of a very well-handled adaptation by Helen Edmundson with music and songs by Neil Hannon - better known as The Divine Comedy - fizzes with spirit and sparkles with invention.

Terry Riley is one of the great unsung heroes of contemporary music, the ur-minimalist who shaped the creative paths of John Adams, Peter Townshend, Mike Oldfield and Philip Glass, to name just a sample of the wide range of musicians who have been inspired by his raga-tinged loops and all-enveloping electronic soundscapes. This week Bristol has hosted a series of exciting concerts celebrating the 75-year-old Californian composer, whose groundbreaking genius feels as fresh today as it first sounded in the 1960s.

When Tony Harrison transposed his version of Molière’s The Misanthrope from the 17th century to the early 1970s, he managed with his characteristic and brilliant combination of savagery and wit to make the play feel totally contemporary. For Andrew Hilton’s new production at the Bristol Old Vic, Harrison has tweaked the play into the 21st century, with characters clutching iPhones and boasting of their connections with Sarkozy. Molière’s masterpiece is about human failings and the reason this classic makes us laugh today is because we recognise ourselves in the characters' parade of foibles.

Bristolians were invited to make history last weekend. The city saw the opening of the Museum of Stokes Croft, a one-room cabinet of contemporary urban curiosities that includes fake neighbourhood relics and archaeological finds, an early Banksy T-shirt, a large, totemistic multi-coloured bear full of mirrored surfaces by street sculptor Jamie Gilman, a cheap plastic urn containing the ashes of “Bear” - a popular homeless street poet who died last year - evocative children’s drawings of local landmarks, quirky fragments of oral history, politically tinged poems, and a map of Bristol’s world-famous underground music scene drawn by Japanese fans, complete with red pencil improvements from “Fat Paul” Horlick, a local music impresario and owner of the Croft, a cutting-edge nightspot a few doors down.