A stringed instrument, for example an electric guitar, is arranged to produce a tremolo effect by providing the tailpiece with a number of saddles corresponding to the number of strings, each saddle having a slot for anchoring its string. The tailpiece is pivotable about an axis substantially perpendicular to the strings in order to change the tension in the strings to produce the desired tremolo effect. The tailpiece includes a housing in which the saddles are provided with a screw adjustment which varies the off-set of the saddle from the axis of the pivot. The greater the off-set of the saddle from the pivot, the greater the extension or release of the string on activation of the tremolo lever to turn the tailpiece. Thus, the position of the saddles relative to each other can be made so that on activation of the lever which pivots the tailpiece, the strings whose tension is changed remain in harmony. If desired, some of the strings can be ‘de-activated’ by adjusting the saddle position so that the string remains on the axis of the pivot so that no change in string tension results as the tailpiece is pivoted.