SVS now sells an adapter to drive any subwoofer that has an RCA input, using a speaker-level connection. I have not tried this product, but it's inexpensive and comes with a home trial period.
Sub woofer naive question day
I am a geezer and have had decent audio equipment for better than fifty years. But have never owned a sub woofer. What is the proper way to implement the speaker into a system with an integrated amp that does not have a specific sub tap? The amp has a line out and a pre out.