I recently purchased the RC-30 Dual Track Loop Station. I have seen videos of people using this pedal and having two separate loops that are of different lengths looping over each other, which everyone else claims is impossible.

For instance, when Ed Sheeran starts beatboxing in this video (around 37 seconds): http://youtu.be/DV0TJZ7Kp40?t=37s

He seems to double the length of the other loop when he's beatboxing. How does he do this, if he is also using a RC-30? Any help?