Hello Petra, if you are playing on a violin that is too small, it should not cause any problems with your vibrato. I can successfully play on a 1/16th size. And the rule is ‘when in doubt, go with a smaller size’ for students considering moving to a bigger size. Your practicing is effective, but if the violin is a lot too small, you’ll have some issues with keeping the bow close. Then, when you get a violin the right size, you’ll need to allow time to adjust, reaching out a little more with the bow arm and the intervals between the fingers will feel wider.
Two things you can still work on that help prepare you for vibrato. 1) Holding the violin with the head only. This is critical for vibrato and shifting. and 2) Not being ‘stuck’ to the violin neck at the base of your left hand first finger. Practice ‘sirens’ to make sure your hand isn’t stuck to the neck.
To size your violin: Put the violin in playing position. Reach the left hand out past the scroll, palm facing you. Place the furthest part of the scroll in your palm. You should still be able to bend the elbow comfortably. If you can, the violin is a good size (unless the elbow is really bent and your hand is feeling close to your face!) If your arm opens and the elbow joint locks, the violin is too big. Playing on a violin that’s too big, makes it harder to play.
I recommend wrist vibrato as it can be done with relaxation. I posted an extensive response in another thread about vibrato. I’ll find the link and put it here.
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