What's it like to hear Gnawa music live?

It usually starts low and unhurried. A maâlem — a master musician — sits with the guembri across his lap, a three-stringed camel-skin bass lute, and plucks out a deep, rolling line that you feel in your sternum before you really hear it. Around him the players lift their qraqeb, those heavy iron castanets, and begin a clashing metallic rhythm that builds and builds, layer on layer, until the whole space is a single pulsing machine of sound. Someone starts to sing, and the others answer, and you realise your own foot has been tapping for a while without your permission.

Gnawa isn't entertainment in the casual sense; it carries the spiritual weight of the sub-Saharan ancestors who brought it north through centuries of trade and slavery, and you can feel that lineage in the music's seriousness. The chants invoke saints and spirits; the colours of the dancers' tunics and tasselled caps each mean something. At a real lila — an all-night ceremony — the music is meant to summon trance and healing, and the rhythms cycle for hours, the tempo winding tighter until people move as though they've handed their bodies over to the drum.

Live, it's overwhelmingly physical. The qraqeb cut the air in fast silver waves; the guembri throbs underneath like a heartbeat; the dancer spins the long tassel of his hat in a blurring circle, head whipping, feet stamping, faster and faster until you can't quite believe a person can sustain it. The crowd claps the offbeat, the maâlem grins and pushes the tempo, and the room tips over some invisible edge into pure momentum. You stop watching and start riding it.

You don't need to understand a word of the Arabic or the older African languages braided through it for the music to work on you. There's a reason musicians from across the world flock to the Gnaoua festival in Essaouira every summer to play alongside the maâlems. You walk out afterwards with your ears ringing and that bass line still looping in your body, having felt — for a couple of hours — plugged directly into something ancient, communal, and very much alive.