When I was in college (University of Connecticut - "Go Huskies!"), my classical piano teacher used to always urge me to "isolate the difficulty" when practicing a piece of music. Of course I rarely took his advice. It's the last thing we want to do: work on the hard parts.
What exactly did my teacher, Leonard Seeber, mean by this? Well, I'd be playing my Mozart or Beethoven sonata, and there would be a tricky spot where I needed to work out a better fingering. Or there would be a series of chords I didn't know well enough, or some inner voice melody that I didn't hear clearly enough. He wanted me to stop playing longer sections for a while and focus on just that one spot.
Of course this is exactly the opposite of what we want to do! We've practiced the piece enough to play it at a good tempo and are starting to really enjoy it. So we kind of gloss over that hard chord or fast scale. After all, who wants to stop playing when we're having so much fun?
Well, I learned the hard way that we do need to slow down sometimes and practice the difficult stuff. Just stop playing the longer sections and identify the exact spot you can't play well. Maybe it's only one chord. Maybe it's the left hand part for 8 measures. Whatever it is, take 15 minutes or a half-hour and do what you need to do. Take that chord apart and play it as an arpeggio, then again as a chord. Slow down those 16th notes and play them staccato, then again legato. Really LEARN that one spot that's tripping you up every time. It might take several days, but make sure you resist the temptation to simply play though the piece while ignoring the work you have to do to learn it thoroughly.
I've gradually come to embrace this approach and am extremely glad I did. Not only have I become a much better pianist by deciding to focus on the hard spots, but I now enjoy doing so. (I never thought I'd I'd hear myself saying that!) I also feel better about my practicing, since I'm facing all of the challenges head on, not just the ones I want to face.
So now I'm passing along my college piano teacher Leonard Seeber's advice to you: "isolate the difficulty." It may take a while, but you'll be very glad you did!
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