As rock music evolved from vinyl records to digital media, it lost more than rich analog sounds and snazzy sleeve art. More crucially, the music abandoned the constrictions under which it had been molded. Where once emerging bands discovered their sound through a series of singles, now artists plunge into CDs and MP3 posts, both of potentially infinite length. With the discipline once imposed by technology stripped away, rock & roll has come to resemble a pretentious kid let loose in a Montessori School.

Imagine the Shapes culls material from four mostly young bands operating under old rules. Each group’s selections were originally released as brief vinyl slabs by the Manhattan label What’s Your Rupture? Not coincidentally, the music retains an energy that’s largely been ceded to the past. This is most immediate in the spastic selections by Brooklyn’s Cause Co-Motion, whose longest number clocks in under two minutes. Yet there are glorious bursts from every quarter. Love Is All, a ferocious sax-fueled quintet from Sweden, invokes the great British punk band X-Ray Spex; England’s Long Blondes turn to Blondie, teetering between chilly pop slickness and underground intimacy; and Comet Gain, whose résumé is littered with numerous members and labels, plays with a sense of mystery that’s becoming more and more rare. Indeed, it’s a quality that seems lost in the grooves of so many singles, unheard, unwanted and undownloadable.—Jay Ruttenberg

Cause Co-Motion plays Bowery Ballroom Thu 15 and Mercury Lounge Mar 3.