1. Replace strings: strings are the source of the sound of a bass. If bad strings, of course difficult to get a good sound. How good / expensive any bass, if strings are mendem ("dead") would sound so bad
2. Know your bass character of us, whether inclined treble, middle, or ngebass (low). From here our reference point. If soundnya not in accordance with our desires, try to correction with tone control / equalizer.
3. There are so many factors affecting the bass sounds, ranging from strings, pickups, body wood, neck & fingerboard.
Try to identify the character masing2, eg the influence of wood types, pickup types, etc..
From there we can determine which one should be modified.
Chain audio a bass sound as follows
Strings-> pickup-> Preamp / Tone Control-> Connection Cable-> Amplifier
Well, just select which one would aja in mod.
Actually the material (wood) body / neck / fingerboard also influence:
String-> Body/Neck/Fingerboard-> Pickup-> Preamp / Tone Control-> Connection Cable-> Amplifier (+ Speaker)
Only if you replace the body just wrote instead of bass.
So, if you can choose a distinguished bass wood is good, Ntar if you want to be upgraded more easily.
If wood is not good (Agathis), although the results are less than the maximum upgrade.