Connecting Bluetooth speakers to aux subwoofer

[Melodiesonmusic]

What is the least expensive means of connecting my aux subwoofer to a Bluetooth soundbar? There’s only one aux in/sub out cord on the soundbar, it accepts Bluetooth aux and RCA.

 

[Alabalcho]

In the same way as you would attach UHaul trailer to a Vette. If the soundbar does not have dedicated sub-woofer connector, you will have to hack it somehow if you want to connect the woofer there.