Want a rewarding, practical, theory lesson? Try transposition.
The great thing about transposition is that you can apply it to whatever level you happen to be at. Are you learning a Chopin Mazurka? Take a phrase and try to play it in every key. Still on simpler pieces? Do the same. Not only will you learn more about the piece you’re working on, you’ll get a deeper understanding of how its elements apply in every key; an understanding that will come in helpful in the future.
Remember to have a good idea of how the piece sounds, and a harmonic understanding of what is going on. (If you don’t understand what’s going on harmonically, get some help with that.) By having this knowledge before transposing, you’ll get an incredible lesson in applied theory, as well as some great ear training. You can often learn more by transposing a small section through all the keys than you can from hours of book study.
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