That horn was no less beautiful on Wednesday night. At London’s Barbican the diminutive Masekela, now 68, picked up the entire London Symphony Orchestra, swirled it above his head and rammed it full of electricity. “It is not true,” he cried in delight, “that symphony orchestras can’t swing.” The concrete acres and bleak empty decks of the Barbican receded and the sandy-coloured wooden walls of the hall took on the shades of the bushveldt.

From student hostels, embassies and enclaves had emerged the capital’s African diaspora. They filled the hall, shouting, clapping, singing and weeping for their hero, Masekela. As he played the great anthem Morija-Maseru, and called out the names of Lesotho, Botswana, Swaziland, Namibia and Angola, cries of ecstatic recognition broke out from the audience. However briefly, he had brought today’s exiles home.

Masekela’s enterprise with the LSO was the brainchild of its remarkable director, Kathryn McDowell. She had not only to marry a jazz trumpeter to a symphony orchestra, which is no longer new, but also rearrange Masekela’s music for classical players, have them play with appropriate rhythm, and make use of the local St Luke’s community choir. Small wonder Masekela described the operation as “a hazardous trip” that had left him “scared stiff”.

He struck gold in his orchestral arranger, Jason Yarde, a Rastafarian Guyanan with a remarkable talent both as saxophonist and composer. In return, Masekela performed the premiere of Yarde’s concerto for trumpet and orchestra, an uplifting piece entitled All Souls Seek Joy. Yarde is a musician to watch. In his work, “world” meets jazz meets crossover to the point where such terms mean nothing. We are left with just glorious music.