The improved tuning mechanisms include a novel string clamp comprising a lever based clamping element oblique to the string path that utilizes an enlarged radiused underside to provide a variable clamping point to address various diameters of strings which can be integrated into either a fine-tuner or Macro-tuner arrangements; further, there, is, in addition to an improved Global-tuner, a fixed dimension multi-tier insert plate for a tremolo base plate, provided in differing sizes, to support bridge elements in a radii that matches various fingerboard radii, and improvements directed towards integrated riser posts for bearing arrangements on the pivot axis of a fulcrum tremolo provide a slotted axel recess and a separate threaded outer sleeve-like portion to allow alignment to the tremolo's bearing axis regardless of the position of riser post within body for adjustably mounting the fulcrum tremolo to the instrument, which, in the preferred embodiment, all work cooperatively together.