the left right RCA preamp outputs of the receiver connect to the subwoofer inputs
OR you can use the left right tape outputs of the receiver, and connect them to the inputs of the subwoofer.http://www.cambridgeaudio.com/assets/documents/S80_Technical_Specification.pdf
you do not need a receiver with a subwoofer output or a subwoofer amp.
The sub you are looking at has a built in amplifier and crossover.
The Cambridge speakers are made to connect to an ordinary 2 channel receiver. You need a "preamp out" or a "tape out."
Do you have either? It's better to have a preamp out..
OR the new receiver needs to have preamp outputs, RCA jacks, on the back of the receiver.
I looked at the Sony Specs and it DOES NOT have preamp outputs.
And so, keep looking for a receiver with RCA type left and right preamp outputs.
The receiver DOES NOT need a subwoofer output, if you are buying the Cambridge subwoofer.