Superstar DJ Calvin Harris seems like he's likely to be using his real name. When DJs change their name, they usually go for something elaborate or influenced by rave culture; Oxide, Neutrino, Avicii, the Chemical Brothers and many more stand as testament to that. So why would you change your name to Calvin Harris if you were, in fact, called Adam Richard Wiles?
The explanation is a little bizarre. When he was trying to make a name for himself, Harris mixed various kinds of music, and his first minor release was a soul track. He thought his real name was 'too white', and so went with the more 'racially ambiguous' Calvin Harris, on the grounds that it might be more acceptable to his intended audience. Those are some murky waters to wade into, and he's been stuck with the name ever since. Whoops!