Savarez - 504J Filé Métal Argenté 4e Blue

The fourth string marks the entry into the low register of the classical guitar: this is where the sound gains in body, where the wire begins to speak, and where the right hand expects a different kind of resistance from the trebles. The 504J's high-crystallinity nylon core vibrates with an organic density that gives extended sustain its staying power - the note stretches without collapsing, carried by the internal mass of the string rather than by tension alone.

The unground surface of the core maintains the natural adhesion between the core and the silver wire: the winding does not slip or shift under the repeated stresses of playing, and the in-process laser control checks the diameter of every centimetre of wire to eliminate irregularities that would cause dead spots along the vibrating length. The resulting great flexibility under the fingers of the left hand reduces the pressure effort, while the response of the string to the attack remains straightforward and the increased volume asserts itself throughout the playing without unbalancing the trebles.

The 504J with high tension covers two classical guitar restocking configurations: Corum basses and Savarez New Cristal trebles. Its blue label identifies it unambiguously on the shelf, and its single-string logic makes it easy to replace the only fourth string.