Well what works for one person will not work for another. too many variables are involved, technique, tension on heads, how long you've been playing and the immeasurable amount of adjustments the 9000's have. Some find a higher spring tension to be the key, others a lower spring tension and higher head tension, some like a higher pedal angle, others lower and so on..it's all personal preference
So the answer to your question is start with one adjustment and play it for a few days to see how it feels then make another.