Iron Maiden singer Bruce Dickinson believes his voice has “a lot more horsepower” since undergoing successful cancer surgery.

“I had a three-and-a-half-centimeter [tumor] — basically a golf ball — living down at the base of my tongue, right at the base,” the rocker explained during an interview with Yahoo. “So, that was sitting there for I really don't know how long by the time it got big enough to notice.”

Dickinson had the tumor removed in 2015, but noted that he recorded Iron Maiden’s LP Book of Souls prior to the procedure. Since then, he’s noticed a world of difference.

“When it went away, I guess there's a lot more space for the sound come out!,” the frontman proclaimed. “Not to put too fine a point on it, but there's no more obstruction in the way, you know? So yeah, with the high notes I was like, ‘Wow! Whoosh!’ There's a lot more horsepower in some of the high notes, which is interesting.”

Dickinson was sure to clarify that this newly enhanced vocal strength didn’t immediately arrive. In fact, it wasn’t until several months after surgery that the singer found his voice.

“In early May [2015], I started trying to sing and it sounded absolutely terrible. I sounded like some wounded beast,” the Iron Maiden singer recalled of his early recovery. “So, I waited another two or three months. I was wandering around the kitchen, waiting until everybody had gone out, and just started to give the voice a bit of a workout. I went, ‘OK, let's have a go at the top.’”

Dickinson tested his voice by running through a few lines of Iron Maiden's classic tune “Run to the Hills.” Sure enough, his voice had returned. “And then I just relaxed, because I'm not in a hurry now; I know it's all there.”

Iron Maiden’s new album, Senjutsu -- the first recorded by Dickinson since his cancer surgery -- will be released on Sept. 3.

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