Tremolo is a rapid back and forth movement of the bow on the same note. Tremolo comes from the word trembling and is an articulation to that nature. When playing soft tremolo you try to use as little bow as possible and when playing extremely strong tremolo you play longer slower strokes with your bow. Always be careful not to over do the intensity of tremolo when playing big symphonies for long periods of time with tremolo. You can easily hurt and tier your arm and shoulder.
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