If you want to master correct playing of duplets against triplets (two against three) try this exercise:
1. Imagine that triplets will become a group of 3 eight notes in 3/8, 6/8, 9/8 or similar meter.
2. Then add an extra sixteenth note to the second note of the triplet, e.g. the entire group will look like this: eighth-sixteenth-sixteenth-eighth.
3. Keeping in mind the rhythm from the previous step, try tapping the triplets with the right hand while tapping duplets with the left hand. Notice how the second note of the duplet in the left hand will be inserted exactly in the middle of the last two notes of the triplet. Practice this group repeatedly (100 times).
4. Repeat the previous step by switching hands. Now the left hand will tap triplets and the right hand - duplets. Practice this version repeatedly (100 times). Shift your focus from duplets to triplets and vice versa and try that each group will sound exactly even.
5. Then take an episode from an actual composition with such rhythms and try to recreate the rhythms you just tapped. If you tried to play duplets against triplets before in this piece, you will notice how much easier the whole business of keeping correct rhythms becomes now.
Use these steps in mastering complicated duplets and triplets in your organ piece today. At first, you may find the task of 100 repetitions daunting but don't worry - since the group of three notes is very short, it will take less than 5 minutes to master.
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