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You won't want to use one of the audio outputs on your Yamaha, sorry to say. Pre-amp outputs have a variable level that is controlled by the volume setting on the receiver, so when you connect that to an amp (that doesn't have a volume control), your receiver will adjust the volume. The audio outputs on your Yamaha are not controlled by the volume setting and would be very loud unless you turn down the gain on the Niles using the knobs on the back, but you'd have no control over the volume except for those gain knobs.