Forty-five years. That’s how long the Canadian-American musician Beverly Glenn-Copeland spent not waiting for fame. Bookending that period are his debut album, released in 1970, and the 2015 rediscovery of Keyboard Fantasies, a record first released on a few hundred cassettes in 1986. In the intervening years, Glenn-Copeland, who goes by Glenn, worked at everything from delivering pizzas to composing for Sesame Street and appearing as a regular on the Canadian children’s TV show Mr. Dressup. 

The one constant was making music in serene obscurity, a process he describes as translating into song the audible transmissions sent to him from the “Universal Broadcasting System.” In the last few years his ethereal music has resurfaced, and his albums Keyboard Fantasies and Transmission...