A Sadowsky pre amp & pickups would definitely be an improvement. However, uneven volume between strings as well as other sound issues might be a result of low quality bridge and nut, bad fret work, poor uneven contact between neck & back fingerboard surface... Many reasons are possible. So, expect an improvement in tone but any basic issue you might have will remain.I've never been happy with the pickups on this bass. It does not have an even volume from string to string even trying different pup hights. The only way to hear the G string is to boost the treble and it sounds tiny and harsh.