Yamaha MMP1 Setup Manual page 69

Next, configure the speaker sets and, in this example, assign the 5.1 channel speakers as A,
Large stereo as B, and Small stereo as C. Choose the first channel of each speaker set as
Destination (Only "A" is in multi-channel format when using Setup Wizard. If multi-channel
format is preferred for B,C or D, make additional changes manually after Setup Wizard is
completed).
[Setup Wizard – Speaker Set Output Settings]
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