This was a concert of two halves, and an intriguing display of how the cutting edge of Latin music has changed over the past three decades. The headliners were Los Lobos, the legendary Chicano band from eastern Los Angeles, who began popularising Mexican American styles decades before Ry Cooder got round to mourning the passing of Chavez Ravine.

This week they released their first-ever live album to celebrate their 30th anniversary, but they shouldn't have bothered, for they are not a patch on the band they used to be (just compare this new set with the exhilarating four-CD retrospective they released four years ago). To add to their embarrassment, they were proceeded at Somerset House by one of the best young dance outfits in Latin America.

Orishas are from Cuba, and specialise in mixing local dance styles with hip-hop. They may have looked like an all-purpose boy band in their T-shirts, caps and shorts, but they were slick, clever and highly original. Backed by live percussion, bass and occasional violin, along with the turntables, they mixed bursts of furious hip-hop (in Spanish) with dance songs and even an a capella ballad on which they proved they could sing as well as they could rap. When they called for a 30-second silence in memory of the bomb victims, the crowd obeyed, then started dancing again.

Los Lobos found all that very hard to follow. Once famous for their range and subtlety, they came on like a noisy, heavy-handed bar-room band, bashing their way through that once- rousing 1980s rocker Evangeline or the once-thoughtful ballad, The Neighbourhood, now lost in a muddy blitz of wailing guitars. They calmed down towards the end as David Hidalgo switched from guitar to accordion, almost doing justice to the magical, slinky Kiko and the Lavender Moon and the finale of Mexican and Colombian dance styles. The encore, Marvin Gaye's What's Going On, would have been inspired if it wasn't the song they often end with.