In music, tremolo, or tremolando, is a trembling effect. There are two types of tremolo.
The first is a rapid reiteration
of a single note, particularly used on bowed string instruments and plucked strings such as harp, where it is called bisbigliando or whispering.
between two notes or chords in alternation, an imitation of the preceding that is more common on keyboard instruments. Mallet instruments...
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