Checking The Input Format - Onkyo TX-NR737 Basic Manual

Checking the Input Format

You can check the audio format of the input signals. While
audio from the player is being input, press DISPLAY on the
remote controller several times to switch the information
shown on the main unit display. If "Dolby D 5.1" is displayed
in Signal format, the Dolby Digital 5.1 ch signals are being
input.
The number of channels is not displayed when the input
signal format is "Dolby Atmos".
Using the Listening Modes
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