Unfortunately milesy is right.

The C1 can be configured to act on the signal sent to its right channel when the volume threshold is reached on its left channel. (ie pan your bass line hard right and pan your trigger (usually a kick) to hard left)

You just have to make sure you place a mono plugin after it in the chain. I like to use ohmboys predatohm to distort the bassline and mono it at the same time always good for a dirty bottom end

P.S. Using a mono bassline will actually benefit the mixing and pressing process aswell and is recommended by alot of people for obvious reasons.