Originally, when instruments were tuned, a distinction was made between choir pitch and chamber pitch. The choir pitch was intended for use in churches; the chamber pitch was introduced because in smaller rooms – „chambers“ – „a more beautiful and manly tone“ was needed for the string and woodwind instruments that dominated there¹⁾. The chamber pitch was therefore a whole tone below the choir pitch.

However, there was no consensus as to how high these notes should be. There were „as many tunings … as cities of some importance in Europe.“²⁾ At the Vienna Court Theater in 1827, the tuning fork sounded half a tone higher than in Leipzig, higher also than in Paris, and about as high as in Petersburg.

Comparisons of measurements also showed that in the 18th century there was a tendency to raise these tones. These measurements became possible at all only after Chladni had carried out pioneering research on vibration in acoustics at the end of the 18th century. Chladni proposed to set the pitch of C at 128 oscillations per second, as he had measured it in Wittenberg (and as it was then also common in Paris).³⁾ This would have corresponded to 432 Hertz for the A.

But in 1816, Scheibler suggested starting from the A at 440 hertz. In 1858, however, the Paris Academy chose 435 hertz, as did the 1885 tuning conference in Vienna.

The consequence of a higher concert pitch for the various instruments (quite apart from the singers, for whom this naturally had dramatic consequences) was also discussed at the time. For stringed instruments, for example, it was argued that Amati, Stradivari, and others had designed their instruments for lower chamber tones, and that higher tunings would lead either to greater tension and thus greater danger to the instruments, or to weaker stringing and thus poorer sound.

Nevertheless, in 1939 the ISA decided to adhere to Scheibler's suggestion and designated the A at 440 hertz as the international standard tuning pitch or concert pitch.

Most orchestras today adhere to 440 Hz as their concert pitch. So Renaissance and Baroque music sounded much lower in their day than in today's performances. However, this does not apply to church music, because this was based on the higher choir pitch.