Check connections on back of Yamaha, if RCA type connection labelled subwoofer out (sub out), then you would hook up a powered sub to this spot. Many powered subs have a right/left input on the back, you may want to check in sub owners manual, often the left gets used if you only are connecting a single cable. This usually will have the label "Mono" on the input.
Next you will need to check the set up on your Yamaha, there usually is a way to tell the receiever that you are using a sub.
If this is not how you have things, you will have to elaborate more about your system.
I have connected 5.1 channel speaker system in my amp.But I am not getting sound from subwoofer...'
Please help me with the connections?Is Powered subwoofer needed for it?I have a seperate subwoofer only....

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