Originally Posted by vanKloot
But seriously... as counter-intuitive as it sounds at first, one thing that can help a great deal is actually to REMOVE some of the low-end from the sounds. Especially the super duper low stuff like below 30hz, maybe even below 50hz. What can happen is a lot of sounds produce energy down there but we don't really hear it consciously, so we think it doesn't matter. But it all adds up and turns into "mud". So rolling off the super lows can make a dramatic difference in the mix, though you might not notice it so much on an individual track.
Also I got some good advice in this form about rolling off some frequencies in like the 250 to 500hz range in one of my recent mixes, and it made a huge difference in clarity and punch but didn't lose any of the "oomph". If you know what I mean.
This is pretty much the same thing I just posted in your track thread, only with even more detail here. Good stuff.
One thing not mentioned is that it would really be effective if you handled your bass and kick separately. Generally, I find that the bass carries lower and that I need to high pass the kick at a higher frequency than the bass. While this isn't always true (like when you have a sub on the kick itself), it generally works. It leaves more room for the bass and actually will cause your kick to speak better as well.