Yeah! J-Station!!!
But as far as the sansamp goes I've got no clue.. like others said compression is your friend.
taken from the recordinginstitute.com website
"Try starting out with a ratio of 4:1, and a fast attack and medium release. I usually use the hard-knee type of compression here since bass is such an attack-oriented instrument. But if you were playing smooth jazz bass, then you may want to try soft-knee. It depends on the sound you are trying to get. "
I normally squash it harder than that, but wadda I know... Try it for yourself.
Rock on!
Pat