Here's your manual
. Check Pg. 9 for correct Sub Woofer connection. Leave the SW=YES
setting as is if you any small speakers in the system. It can be set to SW=PLUS
if you want all bass signals
sent to the Sub Woofer. It should only be set to SW=NO
if no Sub Woofer is connected. Experiment between the YES and PLUS settings and leave it where it sounds best to you.
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