String Action on Bass

I was at my friends house the other day playing his bass and he said that he can adjust the string action without having to adjust the truss bar, which is weird because i want to raise the string action on my bass and make them higher but i keep reading that i have to adjust the truss bar and i don't want to because it costs too much money to have someone do that for me. can someone help?

Jack Carver wrote: Is the bridge adjustable in any way? I'm not too familiar with basses, but on my guitar the bridge can be raised, lowered, tilted, etc.

yes you can use an allen wrench on the bridge to raise the strings but i keep hearing that to do that i need to adjust the truss bar

You can raise/lower the action without touching the truss rod, but odds are pretty good that if you make any substantial change to the bridge saddles you'll want to adjust the truss rod too. Try just adjusting the saddles, if you can't get it to play like you want it to, try adjusting the truss rod yourself. Take it slow (1/4 turn or so at a time, if that), and if it sticks DON'T force it.