"There are a lot of actors who think you can just go on stage and do it — you can't," he says. "You need to project. You can give the most amazing performance on stage but if the audience can't hear you, then it's useless."

"I am a lot more confident about (my voice) being heard now. In London, that was more of a worry. Now there's room for me to do ... to play around with the words and put more color into them, sort of a musicality, to try and give every word its individual identity, I suppose.

"Maybe I am more relaxed this time. I think it's just the fact that I have grown up in the year and a half since we (last) did it," he says. "The other night I got a line wrong, which, for me, was like a dagger because I don't like doing it."

"When you are at the curtain call, smile," he says. "I really object to it when I am sitting there in the theater, watching actors who are in a great play — and they come out and don't smile at the curtain call. I think: 'You are lucky enough to be in a really brilliant play, now show some appreciation for the fact that you are there. Enjoy it.' We're doing 'Equus' and we smile. If you can smile at the end of 'Equus,' anyone should be able to."

"I am sure I will be knackered but I adore filming on 'Potter,'" he says. "I can't wait to get back there."

"In 10 years time, I've no clue where I'll be," Radcliffe says. "Hopefully, still acting. If I'm still acting and still enjoying it, I will be happy. I feel pretty certain that will be the case."