Bass synths.

[The_Laughing_Man]

when you make an eq cut on your bass, try over cutting...then replace those frequencys back with one of the above...then another small cut after to just tidy it up.

nooooooo you are opening up a massive can of problematic worms doing this.
Be very very careful with bass expanders, especially stuff like sonic maximiser.
If you are going to use them, don`t use them to "replace" frequencies, only enhance, and make sure they have a wet/dry.
These things add harmonics that can be difficult, and also can do bad things to the stereo image as well as cause very strange shifts of energy in the low end causing all sorts o fmastering problems and possible muddyness.

Find a synth that already fills the low end adequately, then if need be use some bass enhancement.
The best BAss enhancer/maximiser/harmoniser is NewB by Crysonic, it`s the only one that doesn`t totally screw with the stereo and the way it adds bass harmonics doesn`t produce odd energy changes.
Next best is Elogoxa Baxxpander.