Am I the only one that think that Gwen Stefani from No Doubt and Martha Davis from The Motels have very similar voices? I always loved Martha's sultry, dry tone and Gwen's style is very similar. If you get a chance listen to "Only The Lonely" and then "Don't Speak" and see if you agree with me.
In the sense of - pure voice, I agree, other than the fact that Martha can get "husky" in her lower range and can use it to seem more assertive/aggressive than Gwen. Love, `em both, especially their different phrasing styles. Bif Naked is another rock woman with voice that knocks me out. I'd love to see any combination of them team up on a song.
Listen to "Lessons" by Rush and "Happy Now?" by No Doubt. When Geddy yells in that song it sounds just like Gwen when she says " You've got no one else, you're by yourself".