When Los Lobos first came along in the mid-1980s, with their joyous, infectious mix of roots-rock, country, blues and Mexican music, no one expected that they would later become one of America's most inventive and ambitious rock n' roll bands. But from the early-'90s on, they've continually explored new sounds, from avant-rock arrangements to wobbly, found-object percussion and inspired use of woozy sonic clutter in the studio.

Indeed, the group knocked 'em dead at the Power Center a couple of months ago during the Ann Arbor Summer Festival.

And, at the same time, Los Lobos — who perform at the Arts, Beats and Eats in Pontiac on Friday — have often dug deeper into their Mexican-music roots, releasing a few albums worth of traditional Mexican songs along the way. And sometimes, they've combined two those two musical worlds in a single song, like on this one, "Mas Y Mas," originally released in the mid-'90s, when one music mag anointed them as "America's Greatest Band."

Here, David Hidalgo uses his his soaring, usually plaintive voice to deliver a rush of words, sung in "Spanglish" (a polyglot of Spanish and English common among Mexican-Americans in the Southwest — and especially in East Los Angeles, where four of these guys grew up and still live). (The fifth member, sax player/keyboardist Steve Berlin, is Jewish and a Philly native. Go figure.)

In this live performance of the song at a Crossroads Festival from a couple of years ago, Berlin's rumbling baritone sax duels with Hidalgo's fret-burning guitar bursts, as the band tears through one of their signature, inventive arrangements: the song blows out of the blocks with a whoosh and doesn't let up for a second.

And, note that Bill Murray's willfully goofy introduction of the band causes bassist Conrad Lozano to crack up as the band takes the stage.

Kevin Ransom is a free-lance writer who covers music for AnnArbor.com. He can be reached at KevinRansom10@aol.com.