[3] In 1973 he invented the Heil Talk Box, which was used by musicians such as Peter Frampton, Joe Walsh and Richie Sambora.

[1][5] Heil was also an innovator in the field of amateur radio, and manufactured microphones and satellite dishes for broadcasters and live sound engineers.

[2] He learned how to tune and voice the thousands of pipes in the Wurlitzer, which taught him how to listen and dissect discrete tones, an important skill throughout his several careers.

[5] He was a student of organist Stan Kann and played the Wurlitzer organ in concert halls and restaurants for 12 years.

[10] In his teens he also became an avid amateur radio operator, and began designing and building homemade transmitters, amplifiers, and antenna systems.

In his early twenties, Heil began designing and building theater pipe organ installations in the Holiday Inn North restaurant in St. Louis, playing the instruments six nights a week.

)[2] On February 2, 1970, jam band the Grateful Dead were scheduled to play a concert at the Fox Theater in St. Louis.

Heil, one of the two organists on the Mighty Wurlitzer in the Fox, had been given the large discarded loudspeakers that the theatre had recently replaced with new ones, and he had built them into a new sound system using the Altec Lansing A-4 speaker cabinets.

He replaced the 15-inch speakers with JBL D140s, and added an array of four radial horns and ring tweeters, all driven by McIntosh amplifiers.

"[2] The show was a success and the Grateful Dead asked Heil, his crew, and his sound system to join them on the road.

Heil's setup became a template for modern concert touring sound systems[2] and the 'Heil' brand became ubiquitous in venues across the US.

[13] After Heil toured with the Dead, Billboard reported that a small Midwest sound system purveyor had snagged the position.

They had been experiencing a difficult start to their US tour, and Heil brought a more refined and powerful version of his sound system to their shows.

According to Heil, "We set up two 15-channel Midas consoles together, put speakers in four corners and we were able to fly Roger Daltrey's voice around the room.

"[2] Heil toured with other major acts of the 1970s, including Joe Walsh, Peter Frampton, and Jeff Beck.

He applied science learned from Paul Klipsch, Don Leslie, Martin Wick, and the Bell Labs Fletcher–Munson curves.

[5][16] He taught classes at CES and NAB shows in Las Vegas, Trebas Institute in Toronto and Blackbird Academy in Nashville.

He continued to play the Wurlitzer Organ at the Fox Theater in St Louis, and had a classic car collection, chiefly of 50s Thunderbirds.

[18] Also in 2007, he was invited into the Rock and Roll Hall of Fame to put up a display of his historically important gear, which included the first modular mixing console (the Mavis), his custom quadraphonic mixer (originally used on the Quadrophenia tour), and the very first Heil Talk Box.