Tuning Forks
Study of the frequencies of tuning forks throughout history
Author:
Title 4
Learning objectives :
This activity allows students to discover the historical evolution of the standardization of musical frequencies. She develops sound analysis skills through different frequency measurement methods.
Concepts covered
Sound frequency and pitch; Musical standardization; History of music; Sound waves; Spectral analysis
What students will do :
The student analyzes the characteristics of three historical pitches ('Mozart', 'Philharmonic Pitch' and 'A3') using FizziQ sound analysis tools. Using at least two different measurement methods (oscillogram frequency spectrum fundamental frequency) the student compares the frequencies of the tuning forks establishes their differences then creates a comparative table to understand the historical evolution of musical standardization.
What is required :
Smartphone with the FizziQ application; Recordings of the three tuning forks available in the sound library; FizziQ experience notebook; Headphones (optional) for better listening quality
Scientific background :
A tuning fork is a U-shaped metal instrument that produces a stable frequency when struck, serving as a reference for tuning instruments. The height of the sound emitted depends on the dimensions and mass of the branches. Historically, the reference frequency of A has varied considerably: in Mozart's time (late 18th century) it was around 421-422 Hz; the "Philharmonic Pitch" used in London in the 19th century was very high (around 452 Hz); It was not until 1955 that the International Organization for Standardization set the frequency of A3 at 440 Hz as the world standard. FizziQ offers three complementary tools to analyze these tuning forks: the oscillogram which shows the shape of the sound wave in the time domain and allows the period T to be measured (frequency f = 1/T); the frequency spectrum which breaks down sound into its constituent frequencies via a Fourier transform; and fundamental frequency measurement which automatically detects the main frequency of the sound. Tuning forks produce almost pure tones (mostly sinusoidal), resulting in a dominant peak in the frequency spectrum, sometimes accompanied by low amplitude harmonics. This activity illustrates the importance of scientific standardization and its impact on cultural practices.