There's not that much on it, I didn't double anything, I just laid the vocals over the original track, that's why it sounds doubled, we have pretty similar voices. I know of just one way of removing the original vocals and it's probably going to (*auto edit*) up the whole song. Edited with Cool Edit Pro, put on a bit of echo and Hard Limiting. My microphone sucks anyway, so I try and compensate for the shitty sound.