Hello I am sorry if I couldn't find a similar thread. I have a very budget system with a topping tp30 usb dac with 2 teac speakers and I wanted to introduce a subwoofer, I found a used cambridge sw-120 very inexpensive, I was wondering what would be the best way to connect it ? the dac has only speakers out, sub has only line in. Thank you! images: dac http://www.parts-express.com/Data/Default/Images/Catalog/Original/310-312_ALT_0.jpg sub https://www.cambridgeaudio.com/sites/default/files/styles/lightbox_enhanced/public/product/gallery/sx120-gallery-3.jpg?itok=TfnOLZau didn't buy sub yet...