I'm working on a mix right now where I am having trouble separating all of the instruments so they can cut through the mix. One of my fears is that I may have too many guitar harmonies occurring at once through out the mix. The idea was to have two rhythm guitars panned left and right playing harmonizing rhythms, while the bass played a simpler variation of the melody. Everything was sound great together when it was just the drums, bass, and two guitars, but now that I have mixed the lead guitar in, I am having some trouble getting all of the guitars to sound separate.
At the moment I can tell that there are too many low frequencies in the mix and that the cymbals on the left are washing out my rhythm guitar. I think I can fix these issues on my own. What I am still stuck with though is getting all of my instruments to sound separated. I am not sure if this problem can be fixed with tighter EQ'ing, more compression (which there is not much of on the guitars), a different reverb, or maybe less verb.
What I could use right now are a few tips, or trouble shooting starting points because I am not skilled enough to fix this on my own. I'm having fun trying though.
The track isn't available to listen to it, but....
Since this is the majority of what I mix, a few ideas....
Rhythm guitars, cut everything below 90hz out. That should clean up the low frequencies. Use a slightly different tone for each side. I've done things as simple as using the 6L6s on my RoadKing for the Left, and EL34s for the Right, without changing anything else in the signal chain. I've also had good results using different amps (in my case the RK and an Uberschall) for left and right. Setting them to similar tones.
For the lead guitars, cut everything from 120 down. This will let them cut more, also put more mids in these than you do the rhythms. Use a third amp for the leads, that will help them stand out too. Put a little delay (1/4 note delay, 2-3 repeats) on them, to give them some body. Pan the leads not dead center or hard left right. I like 25% left or right. It still gives them a "up the middle" feel, but gives them some space away from the kick, snare and bass guitar.
Think about the arrangement. If the lead guitar is in the same register as the rhythms, it's going to be tough to get them all to separate. Think about it the way a chamber quartet would think about it. The violin (your lead guitar) plays the higher part, the viola (your rhythm guitars) play the middle parts and the cello (your bass) plays the low part. Just moving the lead up an octave can help get good separation.
The last Pharaoh record I mixed had 3 rhythm guitar parts at all times, usually harmonized, and up to 3 lead guitar tracks in harmony at a time. It is possible to get them to all stick out, but you really have to carve them up a bit with the EQ, and get creative with the panning to get them to all line up.
Also - turn the reverb off on all distorted guitars.