Canon EOS C100 Basic Manual page 9

You can record sound using the built-in mics. A useful tip for the internal
mic is the low cut feature. Select Audio Input > Int Mic Low Cut > Then
LC1 or LC2.
LC1 - Will remove low frequencies and let high frequencies through
LC2 – Good to use in Windy conditions
or connect external mics through the XLR inputs held with the clamp
Use the AUDIO IN switches to select internal or external mics
Basic Guide to the C100
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