Sony DCR-VX9000 Operating Instructions Manual page 54

Adjusting the recording sound
To use external microphone
You can record narration using an external microphone.
Set AUDIO INPUT SELECT to MIC.
Set MIC SELECT to NORM so that you can record with an external microphone but the
built-in microphone will be disabled.
Set MIC SELECT to DUAL so that the external microphone records on the L channel
and the built-in microphone records on the R channel. Respectively, the sound is in
monaural.
MIC
MIC SELECT
AUDIO INPUT SELECT
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