Bryan Ferry and Roxy Music were always hard to categorize. Ferry was boxed in by his devilish good looks; the band, by its undeniable glam image and attitude, which often overshadowed the musical brilliance. Ferry was often described as a rock crooner. The sexy album covers were to die for. But to focus on the glam exterior was to miss the elements of danger and menace Roxy Music possessed, and which Ferry commanded. The music was dense, not teenybopper pop. Grainy concert film footage from 45 years ago is proof that Roxy Music rocked as hard (if not harder) than the New York Dolls, David Bowie’s Ziggy Stardust and “Transformer” era Lou Reed. The common thread that connected these acts was a shared love of tacky stage wear, gratuitous riffing, experimentation, weirdness, an infatuation with dance hall music and the influence of Stooges front man Iggy Pop’s loose, underground phrasing. The San Antonio Express-News caught up with the always dapper and nearly ageless Ferry by email to talk about his legacy and his performance this Monday at the Tobin Center for the Performing Arts.