Pitch
Go to hear a modern orchestra in the UK and the chances are that they will be playing at A440. Hear the AAM in a baroque programme and we will be playing at A415, while for a classical programme we will be at A430. And last month’s Monteverdi programme was at A440. Just what does all this mean?
A440 means that vibrations at a frequency of 440 Hertz are treated as the note A above middle C and that the rest of an instrument (or indeed group of instruments, eg an orchestra) is tuned in relation to that starting point or ‘anchor’. The higher the frequency, the sharper the pitch; the lower the frequency, the flatter the pitch. A415, for example, is exactly a semitone lower than A440.
The concept of a standard pitch is a 20th century one (although there has been a natural convergence throughout the history of Western music), and A440 is the closest thing to a standard pitch, but even now there are national variations, eg A442 is common in the USA and A445 in Vienna. National, or simply regional, variations were that much greater in the baroque era, with for example the norm in France being A392 or lower, while Bach would have been working with organs at A480 in Leipzig and Weimar. Furthermore within the same town there would be differences in pitch between the opera, the church and the home. (Indeed it is said that in order to save money on costly metal, organ builders often shortened the pipes thus resulting in a higher pitched organ).
For an organisation such as The AAM pitch is an important issue, since it affects the choice of instruments for different repertoire in an attempt to create the most appropriate sound that would be recognisable to the composer. This is particularly an issue for wind players, where the length of the instrument is the critical factor in determining its pitch and thus several different instruments are needed to cover a range of repertoire. And it is not only instrumentalists who are affected: the human voice has not changed much physically in the last 400 years, and so there will be times when a soprano will be very glad that her top C is at A415 rather than the version a semitone higher at A440!