Christian Bale: 'I Can Turn my Batman Voice on and off'

Christian Bale says he can turn his Batman voice on and off whenever he likes.

The actor -- who stars as the caped-crusader in new film The Dark Knight -- says he used to go home with a sore throat because he was not used to talking with such deep and gravelly tones, but is now so used to doing it, it has become second nature.

He says, "On the first movie, it took me a while to really get accustomed to it but it's like riding a bike. For the second one, I could just switch on and off any time.

"It does still give me a bit of trouble if I talk like that for too long."

On its opening day, July 18, 2008, The Dark Knight set a single-day box office record of $67.85 million, breaking a record of $59.8 million previously held by Spider-Man 3.

The film, which also stars Heath Ledger, Michael Caine and Gary Oldman, also surpassed the $151.1 million opening weekend record of Spider-Man 3 with an opening of $158.4 million, including a record-breaking IMAX opening of $6.2 million, surpassing the $4.7 million of Spider-Man 3.