Hello Meg!
Let me try to give you some suggestions in the order I would try them.
First, I'd make sure my fingering works for my hand. There are a lot of possibilities, so consult a few friends and a couple of different editions if you need ideas. (Or let me know a specific passage and I'll see what I can come up with.)
Second, check the elbow. When the elbow is locked or the arm is rigid, the wrist and fingers have to do all the work. Sometimes this can get them tied up in knots and hold them back. You want to make sure everything is fluid from the hand to the torso.
Next, check the hand position. The most common culprits are fingers that cave in at the joints, playing the thumb on the knuckle, or playing the little finger on its side. Keep the fingertips energized, the thumb perched on the corner (as in the Fabers' Technique and Artistry books!), and make sure there's a curve under the outside of the hand.
Okay, now that the fingering and technique is set, it's time to practice! Here's what I do:
1) Don't skip the warm-up: get the blood flowing and the fingers loosened up with scales, exercises, or a very familiar piece.
2) Under tempo, but with quick fingers: practice the section at a very slow tempo, but with very quick finger motions. Throw each finger into the center of the key, making sure you don't continue to press.
3) Practice in Dotted Rhythms: it's a cliche, but it works! Play the passages in a long-short dotted rhythm, and exaggerate everything. Make the long notes long and relaxed, and the short notes quick and energetic.
4) Burst Practice: For running 16ths, do one long note and three quick ones. Another variation is to play one long note and seven quick ones. It's a variation on dotted rhythms, and also works wonders.
5) Twice a Day: It often helps me to practice something early in the day and come back to it later for a "refresher." I have no idea why it helps, but it does!
6) Be Musical: Don't play mechanically. When you're practicing, make sure you're paying attention to the dynamic shape, phrasing, and articulation of the passage.
And finally, the two most important tools for improving passagework are Faith and Patience. Unfortunately, there is no shortcut to clean, fluid, fast passagework; but I can guarantee that Faith and Patience will get you there. In your practicing, work with your own technique and your own sound. Don't try to force yourself to sound like a recording you heard somewhere or another pianist you heard at a recital somewhere. Work with what you have, and it will respond.
I hope that gives you a few ideas - happy practicing!
Jason
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"If we continually try to force a child to do what he is afraid to do, he will become more timid, and will use his brains and energy, not to explore the unknown, but to find ways to avoid the pressures we put on him." (John Holt)
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