Glad to see I am not the only one sruggling with it!

Another thing I find helpful is setting up the ProChannel EQ on the Kick and Bass to be complementary.

Basically it's a combination of:

• Quick Grouping where you select both tracks and hold CTRL to do the same thing on both tracks at once. Anything where you want the exact same thing to happen on both tracks at once should be set up this way
• Manual Grouping where you choose Custom and swap values on one track. This is great for settings where you want the opposite thing to happen for both tracks at once

Usually for Kick and Bass I will set the amplitude on two bands to opposites using Manual Groups, and leave the Frequency and Q to Quick Groups. This allows me to tweak both tracks with complementary EQ that I can hear in realtime as I tweak. Most commonly this means boosting the kick around 80 (which automatically cuts the kick there in this setup), boosting the bass around 120 (which automatically cuts the kick there in this setup.) 


To tweak you can try using different EQ modes, since cycling through them changes the way the Q works. I tend to find broader boosts and narrower cuts sound great.

I then tend to cut the low mids a bit in both tracks, often using Quick Groups to cut the same frequencies with one mouse stroke.

It takes a little setup the first time, but adding this to my standard template makes it SUPER fast.

For those that like pictures, I go through the complimentary EQ using the Pro Channel on my blog: http://mezzaninefloorstudios.com/blog/?p=62

RE Tuning the bass track; even when I think it sounds really in tune I run Auto Tune  and am always surprized that it "fits" better and sounds better. So I raise my hand on that one,too.
RE Mattplaysguitar's comments.   How do other recordings sound in that room on those speakers?!?! How does the bass "fit"? on other "records". Make a test CD and play it in your car and on a cheesey little boombox CD player with 18" between left and right!, which is always a great way to reel myself in with reverb! HA! Bass will be the same, no doubt.  
    I have a 1980 G&L L-1000 single pickup with 3 position switch which always seemed HUGE, HUGER and HOLY CRAP to me! So, once I learned about multiband compressors, I use to feel like I couldn't get that bass to fit "easily"(read -quickly).
 Then there's the New York school of mixing the bass track and running a parallel bass copy channel with heavy compression and EQ boosts might give you what you are wanting. Start with the basic (bass ick?) track and mix the other underneath til you find your bliss!

As far as Fender Precision Basses,they can sound muddy,due to the placement of the pickup IMO.

A Fender Jazz style pickup arrangement,has always sounded much cleaner/clearer,or at least on some brands,where they have the standard Precision pickup,but also a treble position Jazz style pickup as well.
Bob

Countless awesome-sounding albums albums have been recorded with fender Precision basses! Unless the style of music that you are recording calls for a very clean/clinical bass with lots of high end (definitely not most styles of Rock!), you cannot go wrong with a P-bass. Definitely have it professionally set up, though - proper intonation is important (and if you have a cheaper Fender or a Squier, upgrade the electronics and pickups). Odd that some here have mentioned using new strings - most people prefer the sound of worn in bass strings.

I don't know if anyone has mentioned this, but another cool trick is (if you use a Drum bus compressor), insert a send on your bass track to the Drum compressor bus (I usually turn the volume down a bit on this send - just want a touch of bass in there, but YMMV).

Old strings loose their intonation.  Have you ever looked at the bottom of an old set of bass or guitar strings? That's right ,, there's a bunch of dents at each fret. There goes your intonation.  The windings get full of crud and they are just plain dull sounding. 
I have yet to meet a good bass player who doesn't change strings when there are obviously worn out.      Thank god they never break..well hardily ever...
 +1 the Leftybob's post.

Nice tip Jeff, thank you. That worked great for me.
Sam

indravayu


Countless awesome-sounding albums albums have been recorded with fender Precision basses! Unless the style of music that you are recording calls for a very clean/clinical bass with lots of high end (definitely not most styles of Rock!), you cannot go wrong with a P-bass. Definitely have it professionally set up, though - proper intonation is important (and if you have a cheaper Fender or a Squier, upgrade the electronics and pickups). Odd that some here have mentioned using new strings - most people prefer the sound of worn in bass strings.

I don't know if anyone has mentioned this, but another cool trick is (if you use a Drum bus compressor), insert a send on your bass track to the Drum compressor bus (I usually turn the volume down a bit on this send - just want a touch of bass in there, but YMMV).

John Paul Jones from that kinda well known band Led Zeppelin preferred the Jazz bass pickups for clarity,but then used flat wound strings for low end guts,after using a Tele headstock Precision for years,the Jazz/Flatwound combo became his workhorse until,an Alembic 8 string,came along,and started getting in the way of Pagey's guitar sound.


All only MO of course,but I'd go with a Jazz Bass any day over a mid range mess of a Precision.....again just MO,and of course,there are these things called "bass" on the EQ section of amps etc,to get any percieved loss of lows from the Jazz pickup arrangement.


Each to their own.
Bob  

+1 for flatwounds :) Almost like old bass strings but a smoother low end and no intonation problems :)