Matt Kwasniewski-Kelvin, the co-founding guitarist of Black Midi who performed on their debut album, Schlagenheim , before leaving the group in 2021, has died, his family announced in a statement via the band’s label, Rough Trade . His death followed “a long battle with his mental health,” according to the statement. He was 26 years old. Kwasniewski-Kelvin took up guitar in primary school, quickly adopting a taste for skater-adjacent punk-pop. His father, who played in a party band,