One of punk rock’s greatest joys is when group members interlock to the point of becoming a visceral, vibrating dance machine. London’s Bloc Party achieve this manic bliss on nearly every track of their superb long-playing debut. Drummer Matt Tong provides enough speedy syncopation for several bands, guitarists Kele Okereke and Russell Lissack lend nervous string interaction, and bassist Gordon Moakes adds suspenseful, propulsive shifts. Pointed pop tunes yelp and cry and tug at your heart even as the band’s rhythmic friction spews sparks at your feet. Singer Okereke is black and Tong is of Asian descent, and together with their pale mates they distill twenty-five years of spiky British rock, from the Cure to Blur to hot Scots Franz Ferdinand. Silent Alarm is dance rock, but highly caffeinated.