A-432

A-432 (also written A=432 or simply 432 Hz tuning) is a reference pitch in which the note A above middle C (A4) is tuned to 432 Hz instead of the international standard of 440 Hz. Every other note moves down with it, so music tuned to A-432 sounds about 32 cents (roughly a third of a semitone) lower than the same music at A-440.

Historically, 432 Hz is one of many reference pitches that musicians used or proposed before the world settled on 440 Hz, and it is often called “Verdi pitch.” Today it is best known as an alternative tuning in ambient, meditation and wellness music, and as the subject of many online claims about health and “natural” frequencies. Most of those claims do not hold up; the history and the acoustics are more interesting than the myths.

What is A-432?

Every tuning system needs an anchor. In modern Western music that anchor is a single note, A4, and the frequency assigned to it is called the reference pitch or concert pitch. The international standard, ISO 16, sets it at 440 Hz. A-432 simply moves the anchor down by 8 Hz. The intervals between the notes do not change: a piano tuned to A-432 in equal temperament is still an equal-tempered piano, just slightly lower overall.

In plain terms: if you and a friend both play the same song, one at A-440 and one at A-432, you will sound out of tune with each other, but each of you will sound perfectly in tune on your own. Most listeners cannot tell which version is which without a reference, although the lower one can sound very slightly darker.

Three ways the term is used

• As a reference pitch: a technical setting on a tuner, synthesizer, sampler or pitch-correction plugin, equal to a shift of about −31.77 cents from A-440.
• As a historical pitch: one of several reference pitches proposed in the 19th century to stop orchestras from tuning ever higher, associated with Giuseppe Verdi and with “scientific pitch.”
• As a wellness claim: a supposed “healing” or “natural” frequency, popular in sound baths, meditation playlists and online videos. This meaning is where most of the myths live.

Names and spellings

“A-432,” “A=432,” “A4 = 432 Hz” and “432 Hz tuning” all mean the same thing. “Verdi pitch” or “Verdi tuning” refers to the same value because of Verdi’s support for a lower pitch (see below). “Scientific pitch” or “philosophical pitch” is a related but different idea, based on C4 = 256 Hz.

History of 432 Hz

Before standards

For most of music history there was no single pitch. Surviving organ pipes, wind instruments and tuning forks show that the pitch of A varied by several semitones from city to city and from church to opera house. Low pitches of around 392 Hz were used in parts of France, while some German church organs stood well above 460 Hz. The baroque convention used by period-instrument ensembles today, A-415, is a modern average of that variety, not a historical standard.

Pitch inflation and the first standards

During the 19th century, orchestral pitch in many cities crept upward, partly because a higher pitch gives a brighter sound in large halls. Singers complained that roles were becoming harder to sing. In response, the French government issued a decree on February 16, 1859 fixing the diapason normal at A = 435 Hz, the first official pitch standard on a national scale. A conference in Vienna in 1885 later endorsed 435 Hz for much of Europe.

Verdi and “Verdi pitch”

Giuseppe Verdi supported the French 435 Hz standard. In an 1884 letter to an Italian government music commission, often quoted in the 432 debate, he is reported to have said that a slightly lower A of 432 Hz would be acceptable for “mathematical” reasons. Some accounts, largely from 432 Hz advocates, say Italian military bands adopted 432 Hz around that time; this is poorly documented. That letter is the source of the name “Verdi pitch.” Verdi did not claim any health effect for 432 Hz; his concern was the strain on singers of an ever-rising pitch.

The road to 440 Hz

• 1834: a conference of German scientists in Stuttgart recommended A = 440 Hz, based on Johann Scheibler’s measurements.
• 1896: British orchestras adopted a “new philharmonic pitch” of A = 439 Hz at 68°F (20°C), reportedly derived from the French 435 Hz standard adjusted for a warmer hall.
• 1926: the American music industry informally settled on 440 Hz, and some manufacturers began building instruments to it.
• 1936: the American Standards Association recommended A = 440 Hz. The same year the US time and frequency station WWV added a 440 Hz tone to help orchestras tune.
• May 1939: an international conference held at the BBC’s Broadcasting House in London recommended 440 Hz. Delegates from France, Germany, the Netherlands, Italy and Britain attended. One practical argument was that 440 Hz is easier to generate electronically than 439 Hz, which is a prime number.
• 1955 and 1975: the International Organization for Standardization published the standard as Recommendation R 16 (1955) and then as ISO 16 (1975).

The modern revival

The current interest in 432 Hz began in 1988, when the Schiller Institute, an organization linked to the political activist Lyndon LaRouche, launched a campaign to return orchestras to “Verdi tuning.” The institute collected signatures from well-known opera singers, including Plácido Domingo, Luciano Pavarotti and Birgit Nilsson, for a petition to the Italian government; a proposal was put before the Italian Parliament in 1989 and was not adopted (The Believer). The same circle also promoted the claim that 440 Hz had been imposed for sinister reasons.

From the late 2000s, the idea spread widely online. Video platforms filled with popular songs “converted to 432 Hz,” and the historical story became mixed with claims about healing, the Earth’s frequency and mathematical harmony with the universe.

How 432 Hz tuning works

The numbers

Pitch is measured on a logarithmic scale in cents: 100 cents make an equal-tempered semitone and 1,200 make an octave. The distance between two frequencies is 1200 × log2(f1 / f2). For 432 and 440 Hz that gives −31.77 cents. Most software rounds this to −31.8 or −32 cents; the rounding error is well below what anyone can hear.

In equal temperament every note is derived from A4 with the formula f = A4 × 2^((n − 69) / 12), where n is the MIDI note number (A4 = 69). Changing A4 to 432 Hz lowers every note by the same ratio, 432/440 ≈ 0.9818.

Note	At A = 440 Hz	At A = 432 Hz
E2 (low E string)	82.41 Hz	80.91 Hz
A2	110.00 Hz	108.00 Hz
C4 (middle C)	261.63 Hz	256.87 Hz
E4	329.63 Hz	323.63 Hz
A4	440.00 Hz	432.00 Hz
C5	523.25 Hz	513.74 Hz

For the full table at standard pitch, see frequencies of musical notes.

What changes on acoustic instruments

The frequency of a string is proportional to the square root of its tension. Lowering pitch by the ratio 432/440 therefore lowers tension by (432/440)² ≈ 0.964, a reduction of about 3.6%. On a guitar this is a subtle change in feel: strings are a little looser and bend slightly more easily. Pianos are usually tuned to a single reference, and moving a whole piano by 32 cents is a significant job for a technician, which is one reason A-432 is rare on acoustic pianos outside dedicated projects.

Wind instruments behave differently. Their pitch depends on the length of the air column and on the speed of sound, which rises with temperature. A useful rule of thumb is that a wind instrument rises by about 3 cents per degree Celsius. An instrument that plays at 432 Hz at 15°C (59°F) would be close to 436 Hz at 20°C (68°F). Wind players can pull out slides or joints a little, but large changes affect intonation across the range, which is why instruments are built for a specific pitch.

What changes in digital audio

There are two fundamentally different ways to get a production to 432 Hz:

• Retune the sources. Synthesizers, samplers and virtual instruments generate their notes from a reference pitch. Setting that reference to 432 Hz (or −31.77 cents) makes them play at A-432 natively, with no processing artifacts.
• Pitch-shift finished audio. A recorded track or a finished mix can be moved down by 31.77 cents with a pitch-shifting algorithm. Good algorithms are very clean at such small amounts, but it is still processing.

The simplest pitch shift is resampling: playing the audio back more slowly. That lowers pitch and tempo together. To reach A-432 the audio has to play at 432/440 of its original speed, about 1.8% slower, so a track at 120 BPM ends up at about 117.8 BPM. This is what many online “432 Hz conversions” do. It is fine for listening, but it breaks tempo grids if the audio is used in a production.

432 Hz and scientific pitch

“Scientific pitch” sets middle C to 256 Hz, so that every C is a power of two (128, 256, 512 Hz and so on). The A that goes with it depends on the tuning system. In equal temperament, C4 = 256 Hz gives A4 ≈ 430.54 Hz, not 432. In Pythagorean tuning, where the major sixth above C has the ratio 27/16, C4 = 256 Hz gives exactly 432 Hz. The two ideas are often merged online, but they only meet in that one tuning system.

432 Hz tuning in practice

Setting up a session

1. Decide before recording. A-432 has to be chosen at the start. Every instrument, tuner and virtual instrument in the session must use the same reference; a 432 Hz guitar against a 440 Hz synth produces obvious beating.
2. Calibrate the tuners. Set each tuner’s reference to 432 Hz, or use a flat or offset mode if the tuner cannot go that low (see Gear below).
3. Retune virtual instruments. Use the DAW’s global tuning where it exists, or set each instrument’s master tune or fine tune to about −32 cents.
4. Recalibrate pitch correction. Auto-Tune, Melodyne and similar tools must use a 432 Hz reference. Left at 440 Hz they treat every note as about 32 cents flat and pull it toward the 440 Hz grid.
5. Label the session. Write the reference pitch in the session notes and file names, so anyone who adds parts later tunes to the same A.

DAW settings

DAW	How to reach A-432
Logic Pro	File > Project Settings > Tuning: the Tune slider detunes all software instruments in cent steps; set it to about −32 cents. Audio tracks must be pitch-shifted separately.
Ableton Live 12	Tuning Systems: load a tuning (.scl or .ascl) and change its reference frequency to 432 Hz. All built-in instruments follow it; MPE-capable plugins follow it when their pitch-bend range is set to 48 semitones. Alternatively, set each device’s fine tune to −32 cents.
Cubase	Set tuning in each instrument, or use MIDI-based microtuning tools; audio is pitch-shifted in the editor.
FL Studio	Set each instrument’s fine pitch to about −32 cents; pitch-shift audio clips with a time-preserving algorithm.
Bitwig Studio	Built-in instruments and MPE-capable plugins can follow microtuning; set their tuning to 432 Hz or −32 cents.
Pro Tools, Reaper, Studio One	Tune instruments individually; move audio by −31.77 cents with a time-preserving pitch-shift algorithm.

Menu names change between versions, so check the current manual of your DAW. The principle is always the same: retune what generates sound, and pitch-shift only what is already recorded.

By genre

A-432 appears mostly in ambient, meditation, new age and sound-bath music, where instruments such as handpans, singing bowls and synthesizers are sometimes built or set to 432 Hz. It also shows up in some lo-fi and independent releases as an aesthetic choice. In mainstream pop, dance, rock and hip-hop the reference remains 440 Hz, and many orchestras tune slightly higher, at 441 to 443 Hz.

Gear and software for A-432

Whether a tool can do 432 Hz depends on how far its reference can be moved. Many pedal tuners were designed for small adjustments around 440 Hz only.

Tool	Reference range	432 Hz?
Boss TU-3 pedal tuner	436–445 Hz	No; use a tuner with a wider range
TC Electronic PolyTune 3	435–445 Hz, plus 432 Hz since a November 2017 firmware update	Yes, with current firmware
Peterson StroboStomp HD and StroboClip HD	390–490 Hz	Yes
Korg OT-120 orchestral tuner	349–499 Hz	Yes
Pitch-correction plugins (Auto-Tune, Melodyne)	Adjustable reference	Yes, set manually
Most software synths and samplers	Master tune in cents or Hz	Yes

Sources: Boss TU-3 specifications, Peterson StroboStomp HD FAQ. For how tuners detect pitch and why reference ranges differ, see chromatic tuner.

Documented examples and false attributions

Many independent artists and meditation producers release music at A-432 and say so in their liner notes. Documented cases among major artists are rare, and several widely repeated claims have no evidence behind them.

• Bob Marley, Jimi Hendrix, John Lennon, Pink Floyd: often listed online as “432 Hz artists,” with no documentation. Small pitch differences on old records are easily explained by tape-speed variation during recording, mastering or transfer. Hendrix often tuned his guitar a semitone down (E-flat tuning), which is a different thing from changing the reference pitch.
• Verdi: supported a lower pitch for singers and mentioned 432 Hz in one letter, but composed and performed at the pitches of his time, including 435 Hz.
• YouTube “432 Hz versions”: most are 440 Hz recordings resampled or pitch-shifted by listeners, not versions made by the artists.

Myths and misconceptions

Myth: “440 Hz was introduced by the Nazis”

The 440 Hz standard has a long, well-documented history that begins long before the 1930s: the Stuttgart recommendation of 1834, American industry practice by 1926, the American Standards Association recommendation of 1936, and the London conference of 1939, which several countries attended. The story that Joseph Goebbels imposed 440 Hz to make people anxious or aggressive has no documentary basis. It appears to trace back to a late-1980s article titled “How the Nazis Ruined Musical Tuning,” which leaned on a 1950 complaint by the French musician Robert Dussaut that French musicians had been excluded from the 1939 conference.

Myth: “432 Hz matches the frequency of the Earth”

The claim usually refers to the Schumann resonances, electromagnetic resonances of the cavity between the Earth’s surface and the ionosphere, excited by lightning. The fundamental is about 7.83 Hz. Doubling it repeatedly gives about 15.7, 31.3, 62.6, 125.3, 250.6 and 501.1 Hz; 432 Hz is not in that series, and the resonance itself varies. An electromagnetic resonance and a sound wave are also different physical phenomena.

Myth: “432 is the frequency of the universe”

A frequency in hertz counts cycles per second, and the second is a human unit, originally a fraction of the day and today defined by an atomic transition. With a different unit of time, the same physical pitch would have a different number. There is nothing in physics that gives 432 cycles per second special status. Claims about water, DNA or cymatic patterns “preferring” 432 Hz are not supported by published physics or biology; cymatic patterns change with any frequency, amplitude and plate shape, and do not single out one value.

Myth: “432 Hz is mathematically purer”

Reference pitch and tuning system are separate. At A-432 in equal temperament, all intervals except the octave are exactly as impure as at A-440. Purer intervals come from other tuning systems (just intonation, meantone, Pythagorean), which can be used at any reference pitch.

Common production mistakes

• Converting by resampling and then using the audio in a session at the original tempo; the tempo has changed by about 1.8%.
• Leaving pitch correction at 440 Hz on a 432 Hz vocal, so every note is dragged about 32 cents sharp.
• Mixing references: a sample pack at 440 Hz inside a 432 Hz production, or a session player who tunes to 440 Hz by habit.
• Judging by memory: comparing a 432 Hz version with a 440 Hz version at different loudness. A few tenths of a decibel can change which one sounds “better.”

What studies have found

A small number of clinical studies have tested music tuned to 432 Hz. They are worth describing accurately, including their limits.

• Calamassi and Pomponi, 2019 (Explore): a double-blind crossover pilot study with 33 healthy volunteers who listened to the same film soundtracks at 440 Hz and at 432 Hz. Heart rate was lower during the 432 Hz sessions (a mean difference of −4.79 beats per minute, p = 0.05); blood pressure and breathing rate showed small, non-significant decreases. The authors called for larger randomized trials (abstract).
• Di Nasso and colleagues, 2016 (Journal of Endodontics): 100 patients having root canal treatment; one group heard music tuned to 432 Hz, the other heard no music. Vital signs were lower in the music group. Because there was no 440 Hz group, the study shows an effect of music, not of 432 Hz specifically (abstract).
• Aravena and colleagues, 2020 (Journal of Applied Oral Science): 42 patients having a tooth extracted, in three groups (432 Hz music, 440 Hz music, no music). Self-reported anxiety fell equally with both tunings compared with no music; salivary cortisol was lower in the 432 Hz group. The groups were small (12 to 15 people each) (SciELO).
• Randomized crossover trial, 2025 (BMC Complementary Medicine and Therapies): 43 cancer patients, 15-minute sessions with a monochord tuned to 432 Hz or 443 Hz. Both improved psychological measures similarly. The authors concluded that 432 Hz produced a more pronounced but not significantly different effect on cardiovascular measures overall (BMC).

Taken together, these are small studies with short sessions, specific settings and mixed comparison groups. They suggest that relaxing music can lower some stress measures, and a few hint at a small difference in favor of 432 Hz that has not been confirmed in large trials. None of them supports claims that 432 Hz heals illness or that 440 Hz is harmful. Listeners who find 432 Hz music pleasant can enjoy it for that reason.

This article is for information only and is not medical advice. Music is not a substitute for diagnosis or treatment; anyone with a health concern should consult a qualified professional.

A-432 vs related terms

Term	What it is	Difference from A-432
A-440	The international standard reference pitch (ISO 16)	32 cents higher; the default for almost all instruments and software
A-415	The modern baroque performance convention	About 101 cents (a semitone) below 440, and about 70 cents below 432
Scientific pitch (C = 256 Hz)	A reference based on powers of two for C	Gives A ≈ 430.5 Hz in equal temperament; 432 Hz only in Pythagorean tuning
Temperament	The spacing of the 12 notes within the octave	Independent of reference pitch; A-432 is usually equal-tempered
Down-tuning (E-flat, Drop D)	Lowering certain strings or the whole instrument by semitones	Changes the notes played, not the reference; see dropped tuning

Standards and references

• ISO 16:1975, Acoustics — Standard tuning frequency (Standard musical pitch): A4 = 440 Hz. There is no international standard for 432 Hz.
• French decree of February 16, 1859: the diapason normal, A = 435 Hz.
• American Standards Association, 1936 and London conference, May 1939: A = 440 Hz (overview).
• Bruce Haynes, A History of Performing Pitch: The Story of “A” (Scarecrow Press, 2002): the standard scholarly history of reference pitch.

Related terms

• A-440: the standard A-432 departs from.
• A-415: the baroque convention, a full semitone below 440 Hz.
• Tuning: the general process of setting instruments to a reference.
• Chromatic tuner: the tool used to tune to any reference pitch.
• Frequencies of musical notes: note-by-note values at standard pitch.
• Overtones: why a lower reference slightly changes brightness.
• Fletcher-Munson curves: why loudness differences distort A/B comparisons.
• Perfect pitch: listeners with absolute pitch often hear 432 Hz music as out of tune.
• Auto-Tune: must be recalibrated for A-432 material.
• Facts about tuning: more history of how instruments are tuned.

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