Asked in 2005 about how quitting smoking affected his singing voice, actor Tim Curry replied:
It's extraordinary. Within about three weeks I gained [some range] at the top of my voice. [...]
Harry Nilsson, I remember, was making that legendary record with John Lennon singing backup. And Danny Kootch, this great guitar player, says to Harry, "What you're doing to your voice is the equivalent of me dropping this grand piano on my guitar." And Harry said, "I grew this voice, man. I'll grow another." And you know, he didn't. But you can if you don't need to sound good.
The great thing about singing is you can project so much personality, even if your voice is trashed.