Could Jack Johnson fill Hyde Park? With a little help from his friends, he packed the place – something neither Eric Clapton nor the Police managed at the weekend. For non-devotees, the scale of Johnson’s success is bewildering.

Few can deny that the former surfer from Hawaii makes pleasant, mellifluous music, but it’s hardly spectacular stuff. Yet in seven years his sales have exceeded ten million, and his current album, Sleep Through the Static, topped the charts in eight countries, including Britain and the United States.

His support act Ben Harper, midway through his set, described Johnson as “the nicest guy I have ever met” and, certainly, you couldn’t fault him as a friend. It was Harper who helped to launch Johnson’s career after hearing an early demo. He appeared on his debut album and took him on tour.

Watching the favour returned, it was hard not to notice how much more mellow Harper has become. The once sombre performer smiled, joked and complimented a fan on her wig. Songs from his current album, Lifeline, forsook his trademark Delta blues for summery folk, although it was a lap steel solo, before the vintage song Welcome to the Cruel World, that got the crowd clapping along.

Johnson’s (label)mates constantly cropped up during the day. Mason Jennings and G Love & Special Sauce played afternoon sets sprinkled with showers and Matt Costa joined him for a duet. Johnson’s sole nod to his star status was a sextet of different-sized video screens, framed like photos, hanging above his band. Otherwise, he was a humble headliner.

Sleep Through the Static is supposedly Johnson’s darkest album to date, though with its laid-back, loping groove, a new song, Hope, the set opener, had all the eeriness of a beach barbecue. Johnson’s problem is that he has only two speeds at his disposal: lazily midtempo and sleepily slow.

Occasionally, a song would stand out – Questions, with its gentle nod to hip-hop, the purposefully poppy Sitting, Waiting, Wishing and Good People, still Johnson’s most distinctive hit.

Much of the rest merged into a long, dreamy, toe-tapping backing track. Or rather, a knee-bending one. A glance around Hyde Park revealed thousands of fans dipping up and down in unison, as though they were at an oversixties exercise class. As an artist to bend to then, Johnson probably is in a class of his own.

Tour continues tomorrow and Sun, Watergate Bay, Newquay; Monday, Manchester MEN Arena

Click here to find tickets for Jack Johnson

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