Los Lobos/Orishas, Somerset House, London

It is a great miscarriage of justice that Los Lobos are mainly known for a somewhat sanitised version of the storming Ritchie Valens classic "La Bamba". The track gave the band the kick-start they needed, but has also been an albatross around their necks for nearly two decades. Their prodigious and adventurous output since has not had the critical attention or sales it richly deserves. But before we find out if these ageing Chicanos from East LA can still cut it live, we have the spring chickens Orishas to get the party started.

Surprisingly, the young Cubans have a stunning pop sensibility. Clearly the hip-hop template is just something fashionable to hang their infectiously catchy tunes on, and in this live context their music starts to make a lot more sense. Three lead singers/rappers, bass guitar and percussion add swing and groove to the laptop breakbeats, and the lilting swoon of Cuban melodies is the perfect foil to the rigid, programmed loops. How many American or British rap artists do you know who can also do immaculate close harmonies? By the end of their set, the crowd are bouncing as one. Orishas are a hard act for Los Lobos to follow.

Things don't get off to a good start. There is rarely, if ever an occasion in rock, or any genre for that matter, when three electric guitars (not including the bass) are strictly necessary - under a barrage of opaque distortion the keyboard was inaudible for the first few songs. Have Los Lobos simply become nothing more than the best pub rock/ blues band in the world?

Fortunately, things get more varied a few songs in, when a cumbia track requires the lead singer and guitarist David Hidalgo to down his Fender Telecaster and embrace an accordion. From then on, it's plain sailing, as the band explore all of the other areas they put into the blender: Cajun, Mexican folk tunes, left-field jazz experimentation, you name it.

Old favourites such as "Dream in Blue", "This Bird's Gonna Fly" and "Kiko and the Lavender Moon" give full voice to their range and talent as songwriters. As Hidalgo, back on Telecaster, tears into the solo on the blinding "Mas y Mas" it's clear that he's one of the world's least acknowledged great lead guitarists.

There are intermittent and irritatingly predictable cries for "La Bamba" from a few audience members throughout the set. Did the band eventually oblige? Certainly not. And credit to them for that.

The encore was instead, a subtle and slightly ramshackle version of Marvin Gaye's "What's Going On". Moving in its unshowiness and resonant in its timeliness, it was the perfect way to end to an evening of two equal but very different halves.