- Martha Novak Clinkscale
A device invented and patented by Sébastien Erard as part of his first repetition action of 1808, which replaced the nut (wrest-plank bridge) and nut-pin (bridge-pin) arrangement of earlier pianos. Érard’s early agraffe resembled a small brass staple with a concave top. One agraffe for each note was attached at a vertical angle to the front edge of the wrest plank, and the strings were passed underneath. Agraffes define one end of the strings’ speaking length and keep them in place by assuring downward bearing on the strings as the hammers strike. An Érard grand piano of ...