William Earl “Don’t you pretend that I’m not alive” were the first words whispered by the Mars Volta vocalist Cedric Bixler-Zavala’s during the group’s reunion stop in New York City on Sept. 29. The tour, in support of a new self-titled record that marks the end of a decade-long hiatus for the Texas rockers, is a reminder not only that the group itself is back but keenly aware of their legacy as a taut, adventurous live act ready to blend genres at a breakneck pace. Their first four records, especially their beloved 2003 studio debut “De-Loused in the Comatorium,” have been a gateway for younger generations of prog fans, fresh to polyrhythms and double-digit song lengths. Yet the band’s final two pre-hiatus albums — 2009’s “Octahedron” and 2012’s “Noctourniquet” — felt like a group in need of a break. This year’s comeback album is perhaps their most far-afield, as it’s their approximation of a pop music, with the average song hovering at three minute mark and produced with a flatter palette than previous work.