Editing Vibrato (section)

== Human perception ==
Currently, the leading understanding is that when vibrato is utilised, listeners are able to focus on the average pitch and hear it as a single fundamental as opposed to the alternation between two different fundamental frequencies.<ref>Nair, Garyth. Voice, Tradition and Technology: A State-of-the-Art Studio. San Diego, Calif: Singular Pub, 1999.</ref> [[Carl Seashore]] (1967) conducted the first comprehensive studies on perceptions of vibrato in the context of classically trained singers, finding some individuals are 50-100 times more perceptive of the presence of vibrato than individuals with the least ability and that “much of the most beautiful vibrato is below the threshold for vibrato hearing and is perceived merely as tone quality.”<ref>Carl E. Seashore, Psychology of Music. New York: Dover, 1967. 46.</ref>  This conclusion was confirmed by [[William Vennard]] (1967) who notes that the listener hears only the average pitch, and the fluctuation is interpreted as enhanced tonal quality.<ref>William Vennard, Singing: The Mechanism and the Technic. rev. ed., greatly enlarged ed. New York: Fischer, 1967. 203; Sundberg, “Aspects of Vocal Vibrato”. 59.; Nair. Voice, Tradition and Technology. 180.</ref>  

In practice, it is difficult for a singer or musical instrument player to achieve only pitch vibrato (where only the pitch or only the volume is varied), and variations in both pitch and volume will often be achieved at the same time. Electronic manipulation or generation of signals makes it easier to achieve or demonstrate pure tremolo or vibrato. In the world of [[electric guitar]] and record production vibrato retains the same meaning as in the classical world (a periodic variation in pitch) but tremolo describes a periodic variation in volume{{dubious|date=March 2020}} usually achieved using outboard [[effects unit]]s.