Watch your levels!
While EQing your bass, another thing to keep in mind is equal loudness contours. Put simply, we (as humans) are more sensitive to upper-mids (1kHz-5kHz) than to lower mids (100Hz-1kHz). We’re least sensitive to the extremes at each end (less than 100Hz and greater than 5kHz). When EQing bass, this means that the lower the frequency, the more level you need. The more level you need, the more you swamp the rest of the mix and the more you need to turn everything down to compensate. It can also cause problems if you’re using compression or limiting on the 2-bus or in mastering.
Similarly, problems can occur further up the spectrum. We are more sensitive to lower mids than bass. In practice, this means that you don’t actually need much level before it sounds like too much. For example, you might find that you can boost a lot of 75Hz before it gets obnoxious, but you can only boost a little at 250Hz before it gets obnoxious. This is also why it usually sounds “better” to dip the lower mids than the bass. The thing to keep in mind, however, is that the lower midrange is where the character of the bass is, whereas the bass is where the body is (and the upper mids is where the articulation usually is).
I can hear the cries – “I WANT CHARACTER AND BODY IN MY BASS!!!”
Yeah. Great. Good luck with that. It’s called the volume fader.
Instead, think about character and body as being a balance. The more character you have, the less body you need to have in order to compensate. Likewise, the more body you have, the less character you need to have. Don’t cry yet. You actually don’t need much character for your bass to be “characterful”, and you don’t actually need much body for your bass to be “thick and deep”. In the context of how it will be percieved by listeners, it’s more a subtle shift of emphasis than a reshaping of the sound.