Why do orchestras tune to an A, and why is the note played on an oboe?
The Australian music educator Kathleen McGuire answers those and other questions in a tutorial on orchestral tuning. Writing for the website The Conversation, McGuire notes that “an open A string [is] common to all orchestral string instruments.” The oboe’s “complex, contrasting overtones, plus a limited yet stable tuning range controlled mostly by a pair of ‘fixed’ reeds” makes it “the practical choice as the tuning instrument.”
Not all A’s are pitched equally, she writes. “An audio frequency of A=440 hertz (Hz) is considered standard or ‘concert’ pitch, although this is a fairly modern concept,” dating from the late-19th and early 20th centuries. And it’s still not standard: Orchestras such as the Berlin Philharmonic and Vienna Philharmonic tune to an A with a frequency of 443 Hz, and the New York Philharmonic to A=442 Hz.
Whatever an ensemble’s standard may be, its pitch is subject to all sorts of variables, from temperature and humidity to mutes on strings, which may “slightly alter the pitch of the instrument.”
And why did Giuseppe Verdi advocate a pitch of A=432 Hz? Read on . . .
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