Viet Cong’s self-titled debut is the kind of album that makes references to certain musical epochs without confining itself to their particular genre conventions. The jangling sounds of a 12-string guitar easily lend themselves to psych sensibilities, but all of that meticulous melody is counteracted by hardened synths and a vacuum-sealed rhythm section, making Viet Cong’s music more comparable to post-punk. Regardless of which label conveniences a particular conversation about the Calgary-based band, it’s obvious that Viet Cong is a majestic ode to mechanistic drumming. Mike Wallace plays a sample pad and drum kit, generating the kind of dependable, propulsive sound that falls down and pulls itself back up. The first time I saw the band, I couldn’t believe that an actual human could generate a sound so precise. Mike Wallace is that good.

When I sidled up to the Mohawk’s outdoor stage to watch Viet Cong play the Pitchfork day party, I was surprised to see Wallace doing soundcheck in a sling, laboriously banging his kit with his right arm, and the band’s frontman Matt Flegel looked nervous. This too was a surprise, because Flegel typically exudes conviction. His confidence on stage is so tangible that it’s practically visible, which made his palpable anxiety yesterday afternoon worrisome. “We are down an arm on our drummer,” he said. “I just want to warn you, but I don’t know if I have to. We’ll see how it goes.”

We didn’t need a warning. With Wallace’s limited mobility and missing sample pad, Viet Cong made space for the audience to hear Flegel’s incomparable, gaunt vocals. Without Wallace’s thunder, Viet Cong’s songs sounded different, but they weren’t lacking. At no point was this more apparent than when the band played their best-known single “Continental Shelf,” which Wallace effortlessly kept up with. Fegel’s wry stage banter was filled with boastful comments about Wallace’s impressive one-armed performance, including one that referenced their recent name controversy. “I want to say that Wallace has his ninja shackles on, but that’s maybe a little bit offensive,” Flegel said with more than a hint of snark in his voice before the band descended into Viet Cong’s eleven-minute closer, “Death.”

About two songs into the set, Flegel admitted that he forgot to tune his bass, assuring the audience that he was too busy worrying about Wallace’s broken hand and their lack of health insurance to remember to prep himself for the show. But Viet Cong proved that this set was just another event in their turbulent career, something that will be laughed about and immortalized by anyone who witnessed the scene. Viet Cong didn’t miss a step. If they did, no one heard it.