Listening to Mariachi El Bronx, you’d never know the music was being played by a bunch of new millennium punk rockers. While the cross-cultural concoctions of Gogol Bordello and Flogging Molly are pots of sound still being melted, this side project of Los Angeles hardcore band the Bronx is fully solidified. Its members play the centuries-old Mexican folk tradition as if they created it. The group’s 2014 release, “Mariachi El Bronx III” on ATO Records is a festive listen using the pluralism of modern culture without genetically modifying the ingredients. It’s a seamless homage free of calculated irony or forced assimilation. Mariachi El Bronx performs at the Broadberry on Sunday, May 17. Richmond skinhead rockers Never Wrong and post-hardcore thrashers Brief Lives kick off the jamboree. Doors open at 7:30 p.m. Admission is $15. thebroadberry.com.