Updated August 23, 2017 Connect the phono plug on one end of the composite audio cable to the yellow-colored phono jack marked “Sub Out” on the back of your Vizio sound bar. Unplug the subwoofer from the wall. Connect the other end of the audio cable to the audio input on the subwoofer’s back panel. It could be labeled “Line-level audio,” “Audio in,” “Receiver in,” “Sub in” or something similar. Turn the subwoofer’s volume control all of the way down, and then plug it back into the wall. Press the power button on your sound bar and on your television set and begin watching it at a normal volume level. Turn your subwoofer’s volume control up gradually until its output blends with the sound from the sound bar. Experiment until you find the right level. Tips Writer Bio
