Here's a thought I just had.... Often I will be working on a mix and I have my vocal in a vocal buss like I normally do. The band mix is good but the vocal just isn't cutting through and my vocal buss is already bumping the red zone. I can't push it further to make it cut through without running into overloading and distortion.
While the best solution is always to set up the arrangement so there are no competing frequencies, that's not always possible.
Another option is
ducking, where you drive the volume of one track with the amplitude of another. So when the vocals go up, the volume of the other track goes down. The problem with this approach is that it'll often lead to "pumping", where you can hear the volume being driven down. The goal is generally to be as transparent as possible.
There's a plugin called
TrackSpacer that's also based a lot like ducking, only it only lowers the volume of the other track where there's a spectral collision. So the effect is more subtle.
Obviously, if you're able to only duck against the instruments there is a collision with, the result will be more subtle.
It's
currently on sale for $40. I haven't used it myself, so I can't speak from personal experience. But I'll be picking it up in the very near future for myself.