With ethnic roots stretching across the Americas, lyrics in Spanish and English, and an effortless mastery of genre-chewing grooves, Los Mocosos are almost as much a concept as they are a musical force. How diverse in sound and makeup can a band be while still retaining their identity? American Us, their second release on Six Degrees, answers with a vibrant declaration of self-definition that's earnestly political and totally infectious. The album is indebted to classic radio, or is perhaps a tribute to radio's globe-shrinking reach, like a playful spin of the dial through the band's influences and intentions. Doo-wop harmonies temper two-tone skank and dancehall toasting of "Hey Mama" to produce a polished, '50s FM radio-meets-'00s barrio sing-along sound. "I'm Your Puppet" is a well-worn radio staple written in the '60s and recorded by everyone from Elton John to Marvin Gaye; Los Mocosos's swinging horns and neck-snapping beat give it a big-band hip-hop twist begging for airplay. The band show their strengths in building upbeat songs perfect for any social setting – "Vete/El largo adios" has slick, club-thumping muscle, while the bottomless reggae bounce of "The Beast" will shake the pavement under slow-rolling car stereos. Homegrown and proud, American Us gets my nomination for San Francisco's official summertime album. Los Mocosos play Sat/28, Independent, S.F. (415) 771-1421. (Jonathan Zwickel)

Crime in Choir
The Hoop (Frenetic)

San Francisco's premier instrumental rock group, Crime in Choir pack fiery punches of overactive jazz, pop, rock, and prog on their second album, The Hoop, with drums, guitars and bass, a Moog synthesizer, a Fender Rhodes piano, and jazz saxophone. The effect is a dazzling weave of impromptu chords that easily flick the mood from creepy horror to downright spacey New Age. The band's beats don't lag behind; their sound is always fresh, and unpredictable. On "Where RR Umbrellas" the drums don't end with a bang as in most rock songs but melt into a satisfied puff that most wouldn't see coming. The Hoop is like a good scary movie teased with classic shock shots and gore saved for the least expected scene. Even without vocals, visual effects are conveyed and interpreted by the listener, leaving the album with an organic, free-spirited quality. People will love or hate The Hoop – the former will appreciate the album because it doesn't stick to form and stretches interpretation; the latter don't want to wait for the suspense. Crime in Choir play Wed/25, Cafe du Nord, S.F. (415) 861-5016. (Stephanie Laemoa) Mail stuff for review to Sarah Han, Bay Guardian Building, 135 Mississippi St., S.F. CA 94107.