I am not a crook's head
Since: Mar 14, 2003
I guess that it depends on what you're trying to accomplish...
I think that an insert is the ideal place for an EQ. This would be on each channel, so that each channel can have its own EQ settings.
If no insert is available, then an aux send/return would work as long as you have the signal mixed at 100% wet, no dry...letting any dry signal thru would defeat the EQ changes.
Putting an EQ after the master out would work as long as you want the same EQ for all channels of the mix.