Johann Scheibler

Johann Scheibler was a wealthy industrialist specializing in textile manufacture, but he also had strong amateur interests in science and music. Amazingly he found time during the 1830s to prove that the average concert A of Viennese concert pianos was 440Hz and also to develop a method for tuning pianos in equal temperament with unprecedented accuracy. In both endeavors he deployed his invention, the tuning fork tonometer , which comprised 56 precision engineered tuning forks. In 1834 the German Academy of Sciences endorsed Scheibler's pitch (the so-called Stuttgart pitch) as the German national standard, but it took until 1926 for this standard to become global.[1]