Connecting an S8 subwoofer to A2+/A5+

Your A2+/A5+ have a variable RCA output located on the rear panel of the left speaker.  This connection can be used to connect an S8 Powered Subwoofer (or any self-powered subwoofer) for extended bass response. You can also add a W3 Wireless Adapter to make this connection wireless as shown below.