Yamaha DSP-A3090 Operation Manual page 31

CONNECTING THE MAIN SPEAKERS TO THIS UNIT
Connect the MAIN speakers to the MAIN SPEAKERS terminals
of this unit. Make sure that the jumper bars between the PRE OUT
and MAIN IN jacks on the rear panel are in place. It is also possible
to use an external power amplifier if more power is desired. In this
Main speaker Main speaker
case, remove the jumper bars and connect the PRE OUT jacks to
the INPUT jacks of a stereo power amplifier with a stereo pin cable—
making sure to connect the left and right channels correctly. Connect
the MAIN speakers to the speaker output terminals of the power
amplifier.
Power amplifier
INPUT
PRE OUT
This unit
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