How do you get a really full bass without swamping everything else or making it louder?
 
Thanks - rev

You don't say what kind of bass you're starting with, so I'm going to assume a good ol' electric bass.
 
I would try either parallel compression (which can make for a volume increase unless backed off) or layering (using your bass MIDI track to drive a synth with the bass preset of your choice), and then blend original and layer a la parallel compression.

I'm sure lots of suggestions will come through, but I'd say a start would be to make sure nothing else clutters your bass instrument(s), first in terms of musical arrangement, then EQ if necessary.  I'm getting better results these days with just a few carefully considered primary parts.
 
Also listen to your song through a single little computer speaker and get the bass behaving there.  That's helped me alot too.
 
 

^^ Mirror EQ is something to get familiar with, which is basically attenuating important frequencies to one instrument on a competing one. Bass and Kick often fight each other for frequency space, since lower frequencies are rarely panned. Using a HPF on instruments is also common if the low end material is not essential to the sound (which will give the bass/kick more room).
 
The first two minutes of this video is a good overview of the above.
 
Edit: At 5:15 in the above video Dan also revisits the bass when the guitars are worked with.

cut the crap out of 300 hz medium q
 

bitman
cut the crap out of 300 hz medium q
 

This^^^^ 
 
But also try mixing just drums and bass first.  Get a big,  full bass sound that does not compete with kick.  Then mix everything else in around that.

Yep - carve out the low end with EQ as shown in the Fabfilter vid.
Also, if you have a clicky kick, go with  thumpy bass, if the kick is thumpy, go with a clicky bass.
 
For a (decently recorded clean) bass in a rock song, a good technique is to clone it, and have one clean track and one kinda crunchy.
Low pass the clean track somewhere around 175 - 350Hz, depending on the tune & track.
Run the other track through an amp sim to add some distortion, and high pass it around the same freq.  
Overlap the crossover as needed and vol balance the two tracks to taste.  
 
That'll get the definition of the primary frequencies + sustain in the overtones. 

Damn good ideas - thanks to all!
 
That vid is very instructive!
 
rev

For me it was a matter of buying a good bass rig. The right bass, PUPS and Pre amps. 
Once you have this,  bass will always sound the way you like it without any post processing. My Bass is compressed going in so I don't often add track compression any more. I record it, set the level in the mix, and forget it. 
Recording is a pleasure if your source sounds are dialed in before you hit the bug red button. It is time better spent perfecting input sound as apposed to turd polishing a so so recording. 

Cactus Music
For me it was a matter of buying a good bass rig. The right bass, PUPS and Pre amps. 
Once you have this,  bass will always sound the way you like it without any post processing. My Bass is compressed going in so I don't often add track compression any more. I record it, set the level in the mix, and forget it. 
Recording is a pleasure if your source sounds are dialed in before you hit the bug red button. It is time better spent perfecting input sound as apposed to turd polishing a so so recording. 

This is soooo true!
 
These days it's all about plugins ... or (plugins)^3 ... but people seem to forget what a difference a good bass player with the right bass makes (it starts with the wood it's made of, pickups, strings and how it's played). find the sound that fits the song before you record and there is not much to do...
 
BTW: I read some old interview with Eddie Kramer the other day and they asked him what special treatments he does to get his guitar sound ... and he said none, because usually guitarists know exactly what they want and they come into the studio with that sound so he just sets up microphones and records ....