Steve Maus’ blog has a good piece on producing vibrato on the violin. I’m a great fan of the arm vibrato, as that way the vibrato comes from the elbow, which gives great mechanical advantage and excellent control – far more than the wrist vibrato favoured in some circles.
Vibrato is the art of making a note waver slightly up and down around the main note, much the way the voice does while singing. It makes the note more interesting to the ear, ad is a great decoration to use on slow tunes or where you have a long note that is not otherwise decorated.
The easy way to practice it is to get a ruler of about 45cm and practice vibrato while stuck at traffic lights or during ad breaks on TV, or during a slow moment at the office.
Just bring your hand up to the playing position, and place your fingers as though they were on a fingerboard. Now make a slight movement from the elbow as though bringing the hand toward you and away from you so that the fingers rock slightly on the ends of your fingers, and keep the wrist fairly straight. This will give you great control because you have the whole arm to provide leverage, making it easy to control the speed and intensity of the vibrato.
Happy Christmas – and happy holidays