Okay, yeah, you can't really tell what someone's voice pitch is from a comic. But in every adaptation of the character I can think of, Batman is given a really deep voice. But he's a bat-themed character. Shouldn't his voice be really high, like a bat's shriek? If Judge Doom can pull it off, why not Batman?
Relevant. http://www.collegehumor.com/video/6643191/batman-chooses-his-voice
"Those are my principles, and if you don't like them... well, I have others."-Groucho Marx