Thursday, 25 October 2012
Annex 2: Pitch Standards from Baroque to Contemporary and Modern music
How has the A above the middle C as tuning reference (also named international standard pitch or concert pitch) reached the standardized A 440 Hz (in the US and UK; in continental Europe the frequency is commonly 442 Hz or 443 Hz) from a state of no pitch standard at all - in which a concert pitch’s frequency could vary in as much as five semitones across the European continent (and very frequently in the same city)?
Actually, in the whole period prior to 1859, there had been no concerted effort to standardize musical tuning.
In the Baroque Era, the note to which ensembles tuned varied widely in time and space. As a result, the pieces notated on a score might have sounded much lower than how they would be performed today. In an effort to correct this discrepancy, many baroque ensembles adjust their tuning pattern according to the repertoire performed: a’ = 415 Hz for late Baroque music, a’= 392 for French music, a’=440Hz for early Italian music and a’ = 430Hz for early Classical repertoire.
Throughout the Classical Period – when the relevance of instrumental, ensemble music became greater than that of vocal works - the tuning reference continued to rise in pitch. This is due to the fact that instrumentalists started competing with each other, each attempting to produce a brighter sound than the others ( the higher string tension caused by a higher pitch tuning actually makes sounds brighter, for the amplitude of the harmonics is larger in higher string tensions). As a result, tuning reference was ‘inflated’ as high as to a’=451Hz.
However, in the XIX century, singers started complaining that the high pitch standard was putting too much strain on their voices, and string instrument performers complained about snapped strings. Due to these protests, the French government decided to pass a law in 1859 setting the A above middle C at 435 Hz, in an attempt to standardize musical tuning. The A 435 Hz became also known as the diapason normal (or French pitch, or Continental pitch, or International pitch – the latter not to be confused with the term ‘international standard pitch’).
Ultimately, in 1939, an international conference determined that the A above middle C be tuned to 440Hz. This A nowadays is also known as ‘concert pitch’. This was adopted as a technical standard by the International Organization for Standardization in 1955 and reaffirmed by them in 1975 as ISO 16. The concert pitch and the diapason normal differ due to confusion over the temperature at which the French standard should be measured.
 Since the purpose of this blog is to discuss topics on classical piano music, this post aims at musical tuning in non-transposing intruments – the group to which the piano belongs. In this context, the term ‘concert pitch’ refers to the general tuning standard of a non-transposing instrument. However, it is also employed to distinguish between the ‘written’ and ‘sounding’ notes of a transposing instrument. Transposing instruments are the instruments of the woodwind and brass section and some string section instruments. In transposing instruments, music is transposed into different keys from that of non-transposing instruments. Therefore, a written C on a B♭ clarinet actually sounds a B♭. In this case, the B♭ is called ‘concert B♭’.
For further information on transposing instruments, see Kennan, Kent Wheeler. The Technique of Orchestration, Second Edition. Englewood Cliffs, New Jersey: Prentice-Hall, Inc., 1970, 1952.