I have a Karera JBC-32 R-Series bass that I have owned for about 5 years now. I have been playing somewhat seriously for about the past 2 years (~1 hour a day) and have come the conclusion it might be time to get a new bass. First, if you have any information about where this bass came from and the general quality it would be much appreciated. I am pretty sure it is not a very quality bass since the truss rod was stripped the one time I tried to have it professionally set up. As a result the bass has never been properly set up. There is one area of the bass where I can't eliminate the fret buzz. I have tried adjusting the saddles and pickups to no avail. The output jack needs to be replaced, the output jack/volume knob cover no longer fits to the screw holes and the pickups are getting rusty despite being stored in a dry room. That's enough ranting about the condition of my bass. My real question is how much of a difference would I notice if I bought a new bass ($300-$500 range)? I have heard the amp makes the biggest difference, but I would have to imagine the bass makes quite a difference as well. FYI, I have a Fender Rumble 100 amp. Thanks.