Justin Adams & Mohamed Errebbaa, The Jam Jar, Bristol review - the African roots of rock'n'roll

Justin Adams has been exploring music that produces trance or near-trance states for a number of years. Along with being Robert Plant’s lead guitarist for a long while, he has followed his own path, seeking out what he had dubbed the secret heart of rock’n’roll.

For a while he played with the Gambian horsehair fiddle virtuoso Juldeh Camara, creating a heady musical brew designed to blow the most guarded minds. More recently, he has worked with the Italian percussion and violin player Mauro Durante, combining blues licks – as he did with Juldeh – with the whirlwind of rhythm and mesmerising repetition that characterises pizzica taranta. For his latest journey he's joined the Gnaoua master and musician Mohamed Errebbaa in order to explore ways of both experiencing the wild energy of one of Morocco’s major healing traditions, and seeing ways in which it can be combined with blues and rock, musical genres that draw their magical strength from roots that include the trance cults of the Maghreb. Errebbaa is a maalem – a master of the Gnaoua tradition, who knows the secrets of provoking trance possession.

The heart of Gnaoua music taps into the heady sound of the gunbri, an instrument with roots in West Africa which arrived in the Maghreb with slaves bought further South. Justin Adams spoke of the first time he was bewitched by the bass throb of this ancestor of the very different banjo. He is not alone in speaking of the way in which, when plucked, the gunbri is known to awaken the spirits around and within us. The Gnaouas wander around North Africa, offering healing rituals, as well as the exorcism of wells, courtyards and homes. These are musical ghost-busters, known for their efficacy.

In Bristol’s Jam Jar, one of the newest of the extraordinary spread of live venues in the city, the Gnaoua experience was taken out of context – as it so often has been. I have been to private events in Essaouira, where a group led by a maalem will offer a kind of psychotherapy to anyone who walks in. These are vibrant events, in which the participants who come for healing are taken to the edge – and sometimes beyond – by master musicians who are expert at provoking altered states. Here in England, the ritual has been converted into spectacle and uprooted. And yet, short of travelling around the Maghreb, this is the best we will get. Justin Adams is no purist and yet, he feels the essence of what this kind of music evokes, and knows as well how it relates to blues and rock.

Some of the material performed here was more authentic, driven by the darkly pulsating gunbri, plucked with great force by the master, accompanied by Driss Yamdah, a young apprentice on the krakeb – metal castanets whose ear-splitting volume and distorted clash is designed to play with the listener’s mind – and versatile percussionist Bala P-D. Otherwise, Adams performed his own bluesy compositions combining them skilfully with the Gnaoua sound, as if he were connecting the ancient past with the music that revolutionised the 20^th century. Some of the material is familiar from previous explorations with Juldeh Camareh and Mauro Durante, but he is in fuller voice now, more confident – so long in the shadow of Robert Plant – and there is something about this mix of Maghreb and Mississippi Delta that feels mostly appropriate.

There are moments when it feels as if Adams's resolute frenzy at times lacks the consummate cool of the maalem who knows that less can be more. But on the whole, the music blazes away; just don't imagine this is an authentic Moroccan Gnaoua ceremony. It is not just a fierce and wonderful lesson in musical genealogy, but an intoxicating marriage of two genres that share a good deal of musical DNA. Time after time, these musicians took the audience on a trip in which time stopped, the insistent rhythms and riffing strings filling the venue with an energy that was as contagious as it was thrilling.

Justin Adams is one of those immensely gifted instrumentalists who’ve not sought, as others have done, the status of guitar hero. He has total command of his instrument, and knows how to make it sing, doubling the role of rhythm and lead. He never plays too many notes, which makes for soulful eloquence. In this setting, inspired by technicians of the sacred, he shines as he never has before.

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