By Daniel Brouse
The standard tuning frequency for A4 (the A above middle C) is 440 Hz. This is known as concert pitch and is widely used as the reference standard for tuning musical instruments in Western music.
History and Adoption:
- 1939: A4 = 440 Hz was proposed at an international conference in London.
- 1955: The International Organization for Standardization (ISO) officially adopted 440 Hz as the standard tuning frequency (ISO 16).
- Historical Variations: Before the adoption of 440 Hz, pitch standards varied widely, with A4 ranging from around 415 Hz to 450 Hz, depending on the region and era.
Alternatives:
- Baroque Pitch: Often uses A4 = 415 Hz, which is roughly a half step lower than 440 Hz.
- Scientific or Philosophical Pitch: A4 = 432 Hz, preferred by some for its supposed natural resonance and healing properties, though this is not scientifically proven.
While 440 Hz is the most common standard today, some orchestras or genres may use slightly higher or lower frequencies for specific stylistic reasons.
432Hz
The claim that 432Hz is the “natural frequency of the universe” and was used by geniuses like Bach and Beethoven to create music that “resonates with the soul” is highly misleading. First, there is no scientific evidence to support the idea that 432Hz is the inherent “natural frequency” of the universe. The universe operates on an immense range of frequencies, from the cosmic microwave background radiation to sound waves in various media, and there is no unique significance to 432Hz within this context. Additionally, attributing this frequency to composers like Bach and Beethoven is historically inaccurate. During their time, there was no universal standard for pitch. Tuning varied widely across regions and periods, typically ranging from A=415Hz to A=450Hz, and there is no evidence to suggest that these composers specifically used or favored 432Hz for metaphysical reasons.
The claim that music tuned to 432Hz “resonates with the soul” is also subjective and not universally experienced. Emotional responses to music depend on cultural, psychological, and individual factors rather than a single tuning frequency. Furthermore, the idea that 432Hz is superior to the modern standard tuning of A=440Hz is based on personal or aesthetic preference rather than scientific evidence. While 432Hz is an alternative tuning that some musicians use for its softer sound, there is no factual basis for attributing any universal, metaphysical, or health-related benefits to it. This statement conflates metaphysical speculation, historical inaccuracies, and subjective preferences to promote an unfounded narrative about 432Hz.
An instrument tuned in standard tuning (A4 = 440 Hz) can play a similar scale to one tuned in scientific pitch (A4 = 432 Hz), but there are some caveats:
- Pitch Difference: The primary difference is that in scientific pitch (A4 = 432 Hz), every note will be slightly lower in frequency than its equivalent in standard tuning. This corresponds to a difference of approximately 32 cents, which is just perceptible to most listeners.
- Relative Intervals Remain the Same: The scale structure and relative intervals between notes (e.g., whole steps and half steps in a major scale) remain unchanged. For example, a C major scale on an instrument in scientific pitch still follows the same pattern as on an instrument in standard tuning.
- Playing Together: If two instruments are tuned differently (one in 440 Hz and another in 432 Hz), they will sound out of tune with each other. However, a solo instrument tuned to 440 Hz can easily transpose to match the “feel” of 432 Hz by adjusting down slightly (approximately 32 cents lower).
Adapting a 440 Hz Instrument to 432 Hz
- For string instruments like guitars or violins, you can simply retune the strings to 432 Hz. This is common for players who prefer the perceived warmth or resonance of 432 Hz.
- For fixed-pitch instruments like pianos or xylophones, you would need to either retune (which is labor-intensive) or adjust electronically (e.g., using a pitch shifter in a recording).
Practical Considerations
- Instruments in standard tuning are versatile and can adjust to play scales that feel like those in 432 Hz. For instance, a piano in 440 Hz can accompany a piece transposed to a slightly lower pitch electronically.
- Many digital instruments or synthesizers allow you to change the tuning standard easily between 440 Hz and other pitches, including 432 Hz.
SUMMARY
Hertz (Hz): The base unit of frequency, equal to one cycle per second
The similarity of scales ultimately depends on their interval structure rather than the exact reference pitch. This means the “scale experience” can be replicated across different tuning standards, as the relationship between notes remains unchanged. Whether you tune A to 440 Hz, 432 Hz, or another frequency, the intervals are what define the scale’s character. While sound waves and frequencies determine the physical pitch, the tuning standard is simply a reference point and does not alter the musical relationships between notes.
In the paper, The Science of Chaos Theory, String Theory, and Music ,you can reference String Theory / M-Theory — “A piano or violin string can resonate or vibrate in various patterns, producing multiple tones simultaneously. These include a fundamental tone and higher overtones (and sometimes lower undertones). The richness and beauty of music arise from the intricate interplay of these harmonics,” explains Edward Witten. (Notice the shape of the strings in the picture. Each string is playing a wide variety of frequencies.)
Music encompasses a wide range of audible frequencies, with live and recorded music differing in frequency range and dynamics depending on the instruments used and the acoustics of the environment. The piano, with its 88 keys, spans nearly the entire range of human hearing (approximately 20 Hz to 20,000 Hz), but music often extends beyond these bounds through techniques like note bending. For example, a blues guitarist may manipulate a single note to produce subtle frequency variations, creating emotional resonance and engaging the listener in unique ways.
In addition to audible frequencies, inaudible frequencies can also have physical effects. Extremely low frequencies (known as infrasound) are often felt in the body rather than heard. These vibrations can create a tactile experience, impacting listeners on a visceral level, such as the rumble felt during a live bass performance or a cinematic explosion.
This interplay between audible and non-audible frequencies contributes to the emotional and physical experience of music, though more research is needed to fully understand the mechanisms behind these effects.
While sound and frequencies can have calming and therapeutic effects, claims of specific frequencies directly causing physical or emotional healing remain largely unproven. Evidence supports broader uses like music therapy and relaxation techniques, but more rigorous studies are needed to validate frequency-specific healing.
CONCLUSION
Since most live music encompasses a wide range of audible frequencies, the specific tuning standard for the A note (e.g., 440 Hz or 432 Hz) plays a relatively minor role in the overall listening experience. What resonates with listeners is the interplay of frequencies across a piece of music, particularly the harmonic combinations of notes—such as the emotional contrasts between major and minor chords—that evoke feelings of joy, melancholy, or tension.
Moreover, the format of the music significantly influences the frequency response. Live performances deliver a full spectrum of sound, including subtle overtones and spatial acoustics, while recorded music, especially if compressed, can alter the richness and range of frequencies reaching the listener’s ears. Beyond tuning and recording methods, the dynamic and unpredictable nature of musical compositions often triggers physical responses. For example, the rising tension, sudden shifts, or crescendos in a piece of music can produce sensations like goosebumps or shivers, a phenomenon linked to the release of dopamine in the brain during moments of heightened emotional engagement.
In essence, while tuning standards provide a framework for harmony, the emotional and physical impacts of music are driven more by its structural, performative, and acoustic qualities than by the exact frequency of any single note. This underscores the complexity of music’s influence on human perception and emotion.