One day a year, the world joins in celebration of Fête de la Musique – a series of free concerts across the globe and open to all kinds of musicians, amateur or professional.

Musicians are asked to perform for no fee, so it’s a great public festival that popularises music of all kinds.

All across the world, players take to streets, parks, train stations and museums, where members of the public or passers by can hear opera, rap, jazz, classical music, rock and more.

This year the Fête de la Musique falls on Saturday June 18, and Phnom Penh is leaping into the festival spirit with a free concert from 6pm at Chenla Theatre, under the auspices of the French Cultural Centre (CCF).

The headline act is French jazz-rap duo 12Mé & Raph – but before that, the CCF is offering an open stage for the first time – a unique chance for local musicians to play the largest theatre in town.

All musical styles are welcome, say the organisers. Several groups have already been invited to open the night, including Klap Ya Handz, an independent hip hop musical family that’s popular among Cambodian youngsters for their modern Khmer lyrics.

Young Australian singer-composer Amanda Bloom is another new face to Cambodia, with a debut album recorded in Sydney, Jordan and London titled The History of Things to Come. With her classical pianist background and an obsession with the European baroque period, Bloom’s other-worldly sounds have been described as Tori Amos in the 18th century.

But it’s the appearance of 12Mé & Raph that will excite lovers of Francophone jazz-rap. The duo have been working with Klap Ya Handz over the past week or so in musical collaboration, and the results should be a spectacular fusion of sounds.

12Mé is a producer-MC who developed instant alchemy with saxophonist Raph when they met a few years ago, and they’ve worked ever since to shake up musical styles and codes into a creative configuration.

Developing the raw boom-bap of the 1990s with sampling from the classical jazz greats of Blue Note, 12Mé & Raph are supported by numerous talented musicians, including a pianist and bass player.

Khmer group Klap Ya Handz with pint-sized rappers Tiny Toones.

Free tickets for Saturday’s concert are available from the CCF headquarters at 218 Street 184, Amrita Performing Arts, 128 Sothearos Boulevard, or Chenla Theatre on the corner of Mao Tse Toung and Monireth Boulevards.