The YSP Bass Out settings are set to Front at the factory to optimize performance if you are not using a subwoofer. There are two ways to turn on the subwoofer output of the YSP. The easiest way is
to run the Auto Setup with the microphone. This will test to see if a subwoofer is connected. The other way to turn on the subwoofer output is to manually change the setting in the YSP Setup Menu
under Manual Setup/Sound Menu. The setting should be changed from Front to SWFR.
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