RIPPLE. Can show up, usually, in the SHELVES.
Primarily, the Low Freq Shelf can play havoc on things like Bass and Kick Drum.
I've been mastering all day/nite, so description words are a bit tired, but listen to the change in interaction/blend, clarity, or twisting in the bottom end.
If an EQ is viewed on an analyzer with proper test tone, it can be seen as 'ripples' [as on water], where the 'expected' smooth sloping is actually a series of oscillating waves, rather than a smooth curve.
Not a great descript, but just a general, unscientific explain.
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