Actually, the 9-pin connector comes from the right speaker and attaches to the the woofer. The woofer has a power cord and a standard audio connector to the computer.
I forgot to mention that the Sony receiver has a connection for both a woofer and speakers. So, I think from what you are saying, is that I should just cut off the audio connector on the woofer as well as the speakers to use the bare wires to make the connection to the receiver?