TX-SR309 speaker problem

I have a pre-existing Kenwood subwoofer that I would like to use with my new Onkyo receiver. The problem is that the sub does not have an RCA jack, just a positive and negative terminal for speaker wire. What is the solution to be able to hook the sub to the receiver using regular 12 AWG speaker wire?

Any help or suggestions would be appreciated. Thank you.

Hi jcobb,
We are looking into this and your other issue and will get back to you soon. Thank you for your patience.

Hi jcobb,
Thank you for your patience. You will need an external amp in order for it to work with your Onkyo receiver. The external amp would connect it to the receiver using an RCA cable, and the subwoofer would then connect to the external amp. Thanks for choosing Onkyo! We will respond to your other question soon.