Donovan's recent enshrinement in the Songwriters Hall of Fame put him in a reflective mood after the ceremony, when he paused during a post-show interview to remember the time he added vocals to Alice Cooper's 'Billion Dollar Babies.'

"He was downstairs and I was upstairs at Morgan Studios when he was doing 'Billion Dollar Babies,'" recalled Donovan. "I had heard this track and he asked me to put a vocal on it and I said 'Sure. But it's so big and so bouncy and so loud, I think I'm going to have to get into a falsetto!' No one believed it was me!"

"I am experimental. I will try combinations that others won’t and have a lot of fun doing it," he explained during an earlier interview. Although he claimed not to know who Cooper was at the time, they met up when "word came up that a band was downstairs and that they would love to meet me. I went down there and Alice had a guitar player in his band that was playing a little bit like Keith Richards and I thought that was fascinating."

After listening to the track, Donovan said he knew he'd need to go for the falsetto because, as he went on to explain, "I had learned by this time, from Chris Squire of Yes, who is a friend of mine, that falsetto was essential for a singer in this type of rock band. It was essential for Jon Anderson in Yes and for Robert Plant in Led Zeppelin. I asked Chris why this was so and he said, 'You have to climb above the guitars. You have to get way up there, as the guitars take up all of the midrange.'"

Once he figured out his approach, "I went in and sang this piercing falsetto and sang, 'Biiillllion dollllar babbbbieeeees.' I can do things with my voice like that," Donovan continued. "Alice said, 'That’s it, man. Let’s record.' I think I did about half the vocals on that song. I have met Alice again over the years. It was really extraordinary to be a part of that song. 'Billion Dollar Babies' went to No. 1. I also did the talking part on the song: 'We go dancing nightly in the attic.' It was all like a horror movie; it was all tongue-in-cheek. I love Gothic mysteries. It has that spookiness."

As Cooper fans know, Donovan could have been just one of many guest stars on the album, if not for some ill-advised indulgences. "Harry Nilsson was there, although [producer] Bob Ezrin had to kick him out of the studio a couple of times for falling onto the control board and moving all the dials," laughed bassist Dennis Dunaway. "I must say, though, that even when Nilsson could barely walk he could still sing beautifully. And Keith Moon was there, along with Marc Bolan, Ric Grech of Blind Faith, and [former Turtles] Flo and Eddie. There’s actually a tape of a jam session we all did, but as far as the music goes, it didn’t come together."

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