What about the entire signal chain before the EQ? Is it up to snuff?
Starting with the vocalist. If he/she does not sound good enough to make a commercial recording when they are singing on their own with no microphone or nothing, no amount of EQ is going to help.
Then there's the microphone. Are you using a high quality vocal mic?
In a decent room?
Is the mic going into a decent preamp?
Is that preamp sending to a decent digital converter or analog deck?
And is the gain staging all along the way tuned properly?
Get all that right, and the compression and EQ necessary to get a good sound will come relatively easily. Get a combination of any two of those off by a considerable amount, and you have a steep, slippery uphill struggle ahead of you, at best.
And cutting sub bass from vocals via shelving or HPF, while it may be good for the purposes of avoiding LF buildup, especially if you are stacking tracks, will have little effect on the vocals themselves; certainly not in the manner of "thickening" them up in any way.
Your ears should tell you what's missing in the character of the sound. If you don't know how to connect in your head what you actually hear to the representitive numbers yet (a waaay too common problem around here), start playing around with either your parametric (preferred) of a 15-band or greater graphic. Start playing with moderate frequeny boosts, starting around 100Hz and slowly working you way up to about 350Hz or so. If you find any frequencies that sound muddy or honky, cut them by a couple of dB. If you find ones that sound warm or rich, and have the characteristics you're looking for, try booisting them by just a couple of dB in turn. But you should (in general) try to do more of cutting the bad freqs than boosting the good ones.
But putting a great vocalist in front of a great mic will get you 70% of the way there first.
G.
