When you are using a powered sub woofer and the LFE/Bass out is set to Both; frequencies from 90Hz ? 20Hz are sent to the sub woofer, as well as the speakers who are set to Large. If you set the LFE/Bass Output to Main, then frequencies from 90Hz - 20Hz are sent only to the Main speakers, only if the Main speakers are set to large. If the Main speakers are set to Small, then only frequencies from 20Khz ? 90Hz are sent to the Main speakers. If all speakers are set to Large, then the LFE/Bass Output is mute.
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