Abstract: A bi-directional vibrato mechanism for use with a stringed musical instrument is capable of being mounted to an instrument body without the need for providing additional holes or recesses in the instrument body for receiving portions of the mechanism. A front part of the mechanism is attachable to the guitar by two mounting posts and includes bridge type support members for the strings. A rear part is pivotally supported on the front part and anchors the lower ends of the strings. Two sets of springs located entirely above the top surface of the instrument body resiliently resist pivotal movement of the rear part relative to the front part in both pivotal directions away from a normal tuned position.

Abstract: A vibrato tailpiece used with an electric guitar is operable to vary the tension of the strings about fundamental tension values and, for occasions when the string tension is so far relaxed as to permit the strings to move loosely relative to their supporting surfaces, the tailpiece includes guide means associated with each string to assure return of each string to its original position on its string supporting surface when it is returned to its fundamental tension. In this way possible de-tuning of the strings due to lateral displacement of them on their string supporting surfaces is avoided.