Rodent said:1. hands/technique
2. preamp
3. hands/technique
4. pickups
5. hands/technique
6. all of the other bass construction materials and techniques which each add a small portion to the overall package
7. hands/technique
I say this due to hearing several of my clients play certain demo instruments I have on-hand. each bass takes on a new sound depending on who is playing it. I hear the same sound consistency when a client switches from one bass to the next ... sure there are subtle differences between different basses, but nothing as extreme as the difference between bassists on a specific bass.
a great player can make a cheap bass sound outstanding ... a poor player can make an outstanding bass sound cheap
Aint THAT the truth. But most people don't realize this. Young or newbie players come on here asking about what bass they can buy to make them sound "metal" or like their favorite pro, or whatever. Much more important than the bass, the musician himself is what makes the biggest difference in tone. I'm not saying I am any super pro, but after playing for 29 years I can play a bass halfway decently. Give me a cheap bass and cheap amp and I can make it sound good. No problem at all. I rarely ever change pickups, have never changed a preamp. I've experimented with a few types of strings though. Because I realize if I want a "different" or "better" tone, I need to play it differently. Use or don't use a pick. Play harder/softer, closer to the bridge or neck or whatever. Go for these things first. MUCH more influential on your sound than changing parts.