Bryston 9B SST2----Stupid Question


I have a Bryston 9B SST2 5 channel amp that is part of an estate that I have agreed to sell for a relative. The owner of the unit is deceased so I cannot ask him this question. No manual.

I'm trying to test it to make sure everything works before I sell it. I've got the speakers hooked up. I've got the pre-amp hooked up.
I just can't tell how to hook pre-amp to the amp. Each of the five channels has two speaker out connects (L/R) but only one single ended or one balanced. How do I plug in the L and R RCA lines out from the pre-amp into the amp?
Sorry to be so stupid about this but I'm stumped.
n80
Got it. That makes sense. Thanks.

Tried it but or some reason that is not working. There could be a dozen things I'm doing wrong. The pre-amp is a Classe Sigma SSP and it is complicated to say the least. I've got a CD player as source into it and I know that part is working because it is playing through the headphone port on the Classe. I'll have to fiddle a little more.