I agree with John.
First off a digital EQ is going to add a bit of latency (delay) while recording so it's probably going to throw your timing off. Analog would be better.
Secondly, you shouldn't commit EQ until you've had a chance to listen to everything in the mix since masking and other issues come into effect during the mixing stage.
That said, there are definitely freqs in a vocal that you won't need, for example adding a high pass filter to kill everything below 85Hz while cutting the vox is fine. That's about all I commit to. Choosing the right mic as John said, along with the right preamp is also critical. If cutting to digital, a tube pre can add some real warmth to a vocal (or a tube mic or tube compressor).
Adding compression while cutting a vocal (if not overdone) can also be helpful especially if the talent lacks good mic technique or they are going from extremely soft to loud in the same track.