Manowar takes its metal very seriously. “When I’m onstage and I see someone smiling,” bassist Joey DeMaio once stated, “I look at them and say, ‘What the hell are you smiling at, motherfucker? This is metal we’re playing!’” Over the past 16 years, Manowar has endured all manner of candyass musical trends by holding fast to the “loud turgid rules” ethos. Declared “the loudest band in the world” by the Guinness Book of World Records in 1987, the defender of the heavy-metal faith has retained legions of fans by upholding one promise: Manowar will never wimp out. “The whole purpose of playing live is to blow people’s heads off, to melt their face, to shake the skin off their bones!” the band’s press release proclaims. Manowar’s early years, peppered with antics like donning Viking warrior costumes or signing their record contracts in blood, lead one to wonder if guitarist Karl Logan might have provided the model for Nigel Tufnel. But any description of the band’s mission pales in comparison with singer Eric Adams’ poetic pronouncement: “The gods made heavy metal/And they saw that it was good/They said to play it louder than hell/And we promised that we would.” With Vertex at midnight at Jaxx, 6355 Rolling Rd., Springfield. $15. (703) 569-5940. (Elisa Nader)