Character "voices"?

When you're reading a book, do you read in what you think each character's voice should be? Or do you just read it all in your own voice?

I think for the most part, I just read all of the characters in my own voice, unless the author distinguishes the voice somehow, either by directly describing the voice, or making it a point to describe a stereotypical character with a unique voice.

Character

I read it on my own voice but I always picture what I think they should look like. That's why 99.9% of the time I am disappointed in whoever they cast when a movie is made.