Eq on vocals can be a bit hard at first. The main reason it’s hard is because of lack of ear training. It is very crucial to know what frequencies sound like, or else you will be playing a guessing game! It also helps to know the common problem areas in a vocal. Those problem areas are low mids and high mids. Low mids make the vocal muddy and high mids make the vocal harsh. When these two areas are controlled, usually everything else falls into place.
Find ear training online that can help you understand frequencies. I actually explain frequencies and what they sound like in my ebook called “The Ultimate Vocal Production Handbook”. Once you know what these frequencies sound like, you will be able to pinpoint the problems you are hearing. Another good thing to consider is that sometimes the vocals are lacking energy somewhere. Maybe they aren’t muddy or harsh but could still use some brightness or some thickness in the mids.
Mids can be a great place to experiment. At times I will boost a db or 2 of an area in the mids. I’ll find a spot around 600 or 700 hz and boost. Then I will byspass the plug in on and off to see if it was an improvement! Often times it is, but certain vocals don’t benefit from it. Watch this video about listening for eq problems here! Another great way to manage eq for vocals is to use multi-band compression! Watch this video for more info about multi-band compression!