Most of the time any band with a female singer will be known for her only. But that's just because most of one's focus in a rock song goes to the words. Rock and roll is so sexual, and the female voice is generally very sexy. Listen to "Wilderness" by Sleater-Kinney, and you'll hear an example. The Pretenders obviously come to mind, but Chrissie Hynde was the main songwriter, too. In my opinion the best female rock singers are those whose voices ooze sexuality... like Janis, Patti Smith, Ann Wilson, etc. But that's what rock is all about, nasty sex. There's just something so hot about a woman getting up there and screaming. Oof.
BTW - Don't say it's sexist to think this way... not all of Robert Plant's appeal to the ladies was his voice (nods towards croch).
If anyone thinks I'm sexist, I'm gonna' go listen to "I'll Stand By You" by the Pretenders and cry.
I read in my book on Sunday afternoon
So it's easy to think the end's coming soon
But though sometimes the signs from heaven are vague
Early November we got back the plague