Vibrato is an essential musical element in string instrument playing that enhances and facilitates expressive performance. However, the acquisition of a beautiful vibrato remains one of the most difficult skills for a young string player to obtain and for instructors to teach. There are many reasons that vibrato is a difficult skill to master. The vibrato motion is complex and only can be executed if the fundamental instrument position and left-hand position are established. Aspects such as appropriate rate, width and purported pitch center are frequently debated (Fischbach, 1998;Gillespie, 1996) and disagreement precludes a universal method for teaching vibrato.In recent years, a team of researchers, including John Geringer, Michael Allen and myself, embarked on a systematic investigation that explored some of the central issues debated by string pedagogues. Through a series of investigations, we explored elements of string players' vibrato, including pitch center, continuity, initial direction of motion, finger employed, positions/pitch register, dynamic level, instrument type and performers' experience level. Although many questions remain, results from these studies provide interesting information to teachers that may be beneficial when describing and designing instruction relative to vibrato. In this article, I will review the research conducted during the last century relative to vibrato performance practice and provide some research-based applications for the studio and classroom.
Pitch CenterPedagogues and artists hold one of three views relative to the pitch center of string vibrato: (1) the frequency of the vibrato oscillates from the in-tune pitch and below (