adding an extension cab to abm c115 500

[la bam]

hi all,

ive just purchased an Ashdown ABM C115 575w combo.

ive been offered a 2x10 ext cab -question is -how would I connect the ext cab to the amp head of the combo?

There is an available speakon socket, but next to that is the pre wired jack plug that connects the amp to the existing 15 speaker. Are these sockets for one output, or is the speakon designated for an extension cab? (so both sockets are being used).

thanks.

[Twincam]

I'm pretty sure you can use both.