Great questions guys! I find that learning vibrato is not so much about your experience level–it’s more about your fundamental habits. If you are struggling to keep your hand back when placing notes down (reaching for notes with tension), this is a bad habit that I always want to correct before introducing a student to vibrato. I’ve seen students have this fundamental down after 1 month, and also seen students not doing it properly after 5+ years. The key is that your hand should be very still when finding notes with your fingers, and then you are in position to achieve a good vibrato.
By doing unnecessary movements/reaching with the left hand, you are trying to build a foundation of vibrato on mud. My suggestion is to have a professional teacher (including myself) evaluate your left-hand technique. If you are ultra-efficient with your left-hand technique, you are ready to start vibrato no matter what experience level you are at.
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