Moody Blues frontman Justin Hayward said their groundbreaking 1967 album Days of Future Passed came about as a result of their record label’s desire for a publicity stunt. The band was signed to Decca, which had developed the Deramic Sound System stereo and wanted a record that could demonstrate it.

“The original idea was by a man named Michael Dacre-Barclay, who was head of special products for Decca,” Hayward told Rolling Stone in a new interview. “Ultimately, I think it was to sell their stereos. They had a consumer division, so they were very interested in trying to turn people who liked pop music on to their stereo units – which I personally couldn't afford. I didn't have a stereo unit until 1970!”

“Basically it was stereo, but people weren't interested at all back then," co-founding drummer Graeme Edge added. "They had a whole series of albums they wanted made to demonstrate the extremes of music. So there was a marching band, a big brass band and stuff like that. They wanted us to play a rock version of Dvorak's New World Symphony with Peter Knight arranging the orchestra. … We persuaded Peter Knight [against it]. At the time we didn't realize what a risk he was taking, but he was a good man. We had nothing to lose, but he had a lot to lose. Still, he went with it. So we recorded Days of Future Passed instead of the New World Symphony.”

Days of Future Passed became one of the first prog-rock albums, as it fused the genre with orchestration. “Back in those days, there used to be two or three acts on a live show, and you had half an hour each," Edge explained. "We were terrible at speaking to an audience, so we had the idea of pulling all our songs together so we didn't have to talk. Basically that was the origin of the idea of Days of Future Passed.”

Elsewhere in the interview, Hayward recalled how he landed his role in the band following the departure of Denny Laine. “I think it was an advantage that I had a Vox amplifier, which was more than they had,” he said. “We were so young. To be quite honest, the only challenges I faced were how to keep up the payments on my guitar and how to avoid going back to live with my parents. There was nothing to worry about, because you don't when you're that young. When you're 19 years old, who cares? I wasn't wrestling with any change in the band's direction or anything like that.”

The Moody Blues will be inducted into the Rock and Roll Hall of Fame this weekend.