Abstract: A tremolo-bridge for stringed instruments, in which the "bridge" and the "tailpiece" can rotate synchronously on one of two fulcrums according to a travel direction of a tremolo arm. Only one fulcrum at a time is involved during a rotation and the only points of friction during operation of the tremolo device are located at these fulcrums. The tremolo-bridge system advantageously includes a main block and a secondary block, each having its own rotation axis. One block has to work as both "bridge" and "tailpiece" and is pivotally mounted on the other block which, in turn, can be mounted on the instrument body. For best adjustment, two sets of countertension springs are provided (one for each block) as well as a differential adjusting device which changes the distribution of spring tension between the two sets of springs, and hence the two blocks, as well as the total spring tension.