Arcam integrateds' have pre-out and pre-in. There is a switch under the cover between the pre amp section and the amp section that needs to be moved to disconnect them internally for what you want to do.
I tried biamping a Classe CA200 with the Alpha10 integrated pre-amp section and it was a bad match. Didn't sound good. Matches very well with Arcam power amps though. I don't know whether I overlooked something when I tried that set-up or not. Just wanted to mention it, so you could research whether or not the integrateds pre-amp section will match well with your sub.
Jim S.
I tried biamping a Classe CA200 with the Alpha10 integrated pre-amp section and it was a bad match. Didn't sound good. Matches very well with Arcam power amps though. I don't know whether I overlooked something when I tried that set-up or not. Just wanted to mention it, so you could research whether or not the integrateds pre-amp section will match well with your sub.
Jim S.