Using an EQ in a subgroup insert - how to apply EQ to a subgroup - Stage Left Audio
EQ Basics: Part 2 of 3 (EQ as an Insert for a Subgroup)
Adding an EQ as an insert to a subgroup works well for controlling a large number of like mics, or fine tuning a group of mics/instruments i.e. a drum kit or a group of backup-singers or other grouped instruments.
Minor changes on the EQ can equate to big noticeable changes for the entire subgroup mics as well as for house sound. Care must be taken when making EQ adjustments.
The trick to good sound...? Set EQ levels very low for frequencies that are not intended for the specific subgroup.