Tuning
Is 432 Hz real?
Real frequency, legend history
432 Hz is a real frequency and a real tuning that some musicians choose for the note A, but it is not a natural, ancient or healing standard. Every concert pitch is an agreement between people: A = 440 Hz was agreed in London in 1939 and became an ISO standard in 1955. The gap between the two is 31.8 cents, less than a third of a semitone, and the only controlled study of 432 Hz music found small, borderline effects in 33 people.
One tuning at a time, picked at random
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Hear them for yourself
Played together, 432 and 440 pulse 8 times a second, the difference between them. Heard one at a time, with nothing to compare, most people are guessing.
The difference
A third of a semitone
Music runs on ratios, not on single numbers. An octave is a doubling, split into 12 semitones of 100 cents each. The gap between two pitches in cents is 1200 × log₂(f₂ ÷ f₁). For 440 and 432 that gives 31.8 cents, about 0.32 of a semitone. Retune every note by the same ratio and every chord, scale and melody stays the same, just slightly lower.
That is why 432 Hz music is easy to make: take a song recorded at 440 and slow its pitch by 1.8%. It is also why the choice only matters when you play along with other instruments. A 432 guitar and a 440 piano will clash.
The “Verdi tuning” sums do not quite work. Its fans pair A = 432 with C = 256, the “scientific pitch” proposed by Joseph Sauveur in 1713. In the equal temperament every modern piano uses, C = 256 puts A at 430.54 Hz, not 432. The two only match if you switch to an older Pythagorean ratio of 27 to 16, and 256 × 27 ÷ 16 is exactly 432.
History
Pitch wandered for centuries
The tuning fork was invented in 1711 by the English musician John Shore. The forks that survive show how far “A” drifted. A 1740 fork associated with Handel sounds A = 422.5 Hz, one from 1780 gives 409 Hz, and Beethoven’s fork from around 1800 gives 455.4 Hz. In Paris, an 1810 opera fork gives 423 Hz, an 1822 fork 432 Hz and an 1855 fork 449 Hz. There was no single ancient pitch to go back to.
440 is older than most people think. In 1834 a meeting of German scientists in Stuttgart approved Johann Scheibler’s A = 440. France fixed A at 435 by law on 16 February 1859, the “diapason normal,” and the 1885 congress in Vienna spread 435 across Europe. The US music industry settled on 440 informally in 1926, the American Standards Association recommended it in 1936, and in May 1939 delegates from France, Germany, the Netherlands, Italy and England met at Broadcasting House in London and agreed on A = 440. ISO made it Recommendation R 16 in 1955 and ISO 16 in 1975.
What Verdi actually said
Giuseppe Verdi first backed 435, the French pitch. In 1881 he sent Arrigo Boito to argue for 432 at a congress of Italian musicians in Milan, and a letter of his was quoted in an 1884 decree:
If the musical commission instituted by our government believes, for mathematical exigencies, that we should reduce the 435 vibrations of French tuning fork to 432, the difference is so small, almost imperceptible to the ear, that I associate myself most willingly with this.Verdi, as printed by EIR, 1988
The 1884 decree came from the Italian War Ministry and set A = 432 for military and orchestral bands. Italy had no time to adopt it nationally before Vienna voted for 435 the next year. The name “Verdi tuning” came much later, from a 1988 campaign by Lyndon LaRouche’s Schiller Institute.
The health claims
One small study
In 2019 Diletta Calamassi and Gian Paolo Pomponi played the same film soundtracks to 33 volunteers, tuned to 440 on one day and 432 on another, without telling them which. With 432 they found a “marked decrease in the mean of heart rate (-4.79 bpm, p = 0.05)” and slight falls in blood pressure and breathing rate that were not significant. They called it a pilot and asked for a larger, randomized trial. A result of p = 0.05 in 33 people is right on the line, and it has not been repeated at scale.
The 528 Hz “healing frequency” rests on even less: a 2018 study of nine healthy adults, not blinded, compared with 440 rather than 432. Its authors say the sample “was limited.” There is no scientific evidence that music at either pitch heals anything.
“The Nazis imposed 440 in 1939”
The Schiller Institute claims Joseph Goebbels organized the 1939 conference. Reuters rated the story false and traced it to an article from 1988. The meeting was at the BBC in London, and 440 had been approved in Stuttgart in 1834 and recommended in the US in 1936.
“Hendrix, Marley and Prince recorded in 432”
Even a writer who favors 432 tuning found no studio logs for any of them. The 432 versions online are fan uploads slowed down from 440 masters.
“432 matches the Earth’s heartbeat”
The Schumann resonance, often quoted as 8 Hz, is around 7.83 Hz and drifts. 432 is 54 × 8, but doublings of 8 run 256, 512, never 432, and 432 ÷ 7.83 is not a whole number.
Real vs legend
432 Hz, sorted
| Claim | Status |
|---|---|
| 432 Hz is a real tuning choice with a real history. | Real |
| 432 and 440 are less than a third of a semitone apart. | Real · 31.8 cents |
| Verdi demanded 432. | Partly · he asked for 435 first |
| Italy made 432 law in 1884. | Partly · bands only, overtaken in 1885 |
| 432 Hz lowers your heart rate. | One pilot study · 33 people |
| 432 was the ancient, natural pitch. | Legend |
| Goebbels imposed 440 in 1939. | Legend · Reuters: false |
| 432’s digits add to 9, so it is cosmic. | Legend · every multiple of 9 does |
Questions
432 Hz
Is 432 Hz bad for you?
No study we found reports any harm. The one controlled trial, of 33 people in 2019, found a slightly lower heart rate with 432 Hz music. It is simply 31.8 cents lower than standard tuning, which only matters if you play along with instruments tuned to 440.
What famous songs are tuned to 432 Hz?
We found no verified classic recordings. Claims about Hendrix, Bob Marley, Prince and others have no studio evidence behind them, and the 432 versions online are fan uploads slowed down from 440 recordings. Only a release from the artist or label itself can be trusted.
Which is better, 432 or 528 Hz?
Neither has strong evidence. 432 Hz has one small pilot study with a borderline result. 528 Hz rests on a 2018 study of nine people that was not blinded and compared it with 440, not 432.
Did Michael Jackson use 432 Hz?
We could not confirm it. We found no reliable source either way, only social media posts. Most 432 versions of famous songs online are slowed down copies made by fans.
What is God’s frequency in Hz?
It is not a scientific term, and no frequency has a claim to it. The popular list of “healing” or “Solfeggio” frequencies traces back to a 1999 book by Joseph Puleo and Leonard Horowitz, not to research.
Why do orchestras use 440 Hz?
Because it was agreed. Delegates from five countries chose A = 440 in London in May 1939, and ISO made it a standard in 1955 and again in 1975. In practice many orchestras tune a little higher, the Berlin Philharmonic at 443, and many Baroque groups use 415.
Sources
Where this comes from
- A440, from Stuttgart 1834 to ISO 16: Wikipedia.
- Concert pitch, historical tuning forks and modern orchestras: Wikipedia.
- Scientific pitch, C = 256 and the Schiller Institute campaign: Wikipedia.
- Ellen Lockhart, “Tuning Sounds in Italy, 1750 to 1885,” Nineteenth-Century Music Review 22 (2025): Cambridge (PDF).
- “Revive Verdi’s tuning to bring back great music,” EIR, 12 August 1988, with Verdi’s letter: PDF.
- Calamassi and Pomponi, “Music Tuned to 440 Hz Versus 432 Hz and the Health Effects,” Explore, 2019: PubMed.
- Reuters fact check on the Nazi 440 story, via the Jerusalem Post, 2021: Jerusalem Post.
- Roel Hollander on the 432 artists myth, 2014: roelsworld.eu. On Solfeggio frequencies: Sound Medicine Academy, 2026.
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