Canon EOS 6D Instruction Manual page 219

Using the microphone

The built-in microphone records monaural sound. Stereo sound
recording is possible by connecting an external stereo microphone
(commercially-available) equipped with a miniature stereo plug (φ3.5
mm) to the camera's external microphone IN terminal (p.20).
In Basic Zone modes, the settings available for [Sound recording] will

be [On/Off]. If [On] is set, the sound-recording level will be adjusted
automatically (same as with [Auto]) and the wind filter function will take
effect.
The sound volume balance between L (left) and R (right) cannot be

adjusted.
Both L and R record audio at a 48 kHz/16-bit sampling rate.

3 Setting the Sound Recording
219