Other than bass drum/bass guitar/etc, apply a low cut (high pass filter) on all your tracks to around 100hz.
Sorry, but that's not how you mix. I keep seeing people (here and elsewhere) talking about how you should just slap an HPF filter on a track to cut the lows. What?!?! No.
Then I keep seeing people (here and elsewhere) talking about how you should just slap an LPF filter on a track to cut the his. What?!?! No.
That's not to say that filters should never be used, nor that there aren't situations where you would just slap an HPF or LPF on and cut. Sure there are. But telling someone who is having an issue getting a vocal track to sit in a mix to slap on an HPF to everything other than bass drum/bass guitar/etc (what's "etc", anyway???) because those tracks "don't need the low frequencies" is not helping - it's hurting. I am really not trying to be a *a no no* here (in real life, I happen to be a really cool guy) but you are telling someone to do something a certain way which is - at least in a general sense - just plain wrong.
If the vocal track is not sitting right in the mix, there are several things to keep in mind.
1) The recording is key. Obviously you are past that point now, but for future reference... capturing a great vocal performance is not just about setting up a mic in front of the vocalist and pressing record. It is actually a lot more involved than many people - including those who are relatively new to engineering - realize. It starts with the vocalist. If the vocalist is not that good (and no, I am not only talking about pitch), you are going to have issues with trying to get that vocal track to sit properly in the mix, regardless of the room, mic pre, mic, compressor used, and regardless of what you do to it - and the rest of the instruments - after the fact. There is the compressor. It's not just adding a comp to the chain - it's knowing how to use that comp. And the settings will vary from vocalist to vocalist. Then there is the room, and the mic pre. Now, the comp, mic pre and room are little things, but they add up. Then there is the mic. Want a good read on how to go about selecting "the right vocal mic"? Have a look at the GS thread, where James Lugo tries to find the right vocal mic for himself:
If you are into audio, and engineering, and you dont find that an interesting read, you need to have your head examined.
2) The dual comp idea is a good one - sometimes . It depends largely on the recording and the performance. Is the performance extremely dynamic to begin with? Was there a comp used already, which has already significantly decreased the dynamic range? Dual comp may not always be the way to go - but if you do decide to go that route, be gentle.
3) Maybe the issue is not the vocal track, but everything else. Or maybe some things. Remember - the vocal track rules all. Well, generally speaking. Sometimes, you need to sacrifice other elements to get the vocal track to sit right. So, the guitar(s), or the snare, or the piano, or whatever, may sound great on their own, and may sound great in the mix without the vocals, but that doesn't mean you should say "well - the guitars sound great - so I can' touch those!" No. If you have to sacrifice some of the guitar for the sake of the vocal, you do it. If you have to cut some freqs from the guitar that are competing with the vocal, but find that the guitar doesn't sound as great anymore, you do it - for the sake of the vocal. That doesn't mean that other things should start sounding like crap; the overall objective is to get the track as a whole to sound great, but sometimes, you have to cut your hand off so you can see where you are walking so as not to walk off a cliff. Ok, that was pretty stupid - but you get the drift.
4) Try backing off on some of the vocal track's reverb level, and when you add a delay, add that same verb to the delays themselves. Try a Ping-Pong delay, so as not to have the delays repeat in the center only.
5) EQ is the way to go when it comes to making something stick out. I cant tell you which way to go obviously, but many many hours have been spent in many pro studios by many a pro engineer working on getting the EQ of the vocal track just right. If you slap on an EQ to the vocal track , and think you are done after spending 5 min on it, you probably have not spent nearly enough time.
Mixing is an art form unto itself, and take many many years to perfect. Keep banging away!