Zoom F8n Pro 8-Input / 10-Track Multitrack Field Recorder - Manual (Page 66)

Inverting the input phase (Phase Invert)
The phase of the input signal can be inverted.
This is useful when sounds cancel each other out due to mic positioning.
1.
Press .
This opens the Menu Screen.
2.
Use to select “INPUT”, and press .
3.
Use to select “Phase Invert”, and press .
4.
Use to select a track, and press .
HINT:
Select “All” to set all the tracks at the same time.
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