ContextThe current reference frequency for tuning musical instruments is 440 Hz. Some theorists and musicians claim that the 432 Hz tuning has better effects on the human body, but there are no scientific studies that support this hypothesis.ObjectiveTo identify differences in vital parameters and perceptions after listening to music at different frequencies, 440 Hz versus 432 Hz.
Cross-over pilot study.Setting
A room dedicated to listening to music, in an Italian city.Participants
33 volunteers, not suffering from acute and/or chronic diseases.Interventions
Two sessions of music listening on different days. Both sessions used the same music (movie soundtracks) but tuned to 440 Hz on one day and 432 Hz on the other. Each session consisted of 20 min’ listening.Main outcome measures
Vital parameters (blood pressure, heart rate, respiratory rate, oxygen saturation), perceptions (physical and emotional sensations, for example fatigue and stress), levels of concentration during the listening session, and general satisfaction with the experience.Results
432 Hz tuned music was associated with a slight decrease of mean (systolic and diastolic) blood pressure values (although not significant), a marked decrease in the mean of heart rate (−4.79 bpm, p = 0.05) and a slight decrease of the mean respiratory rate values (1 r.a., p = 0.06), compared to 440 Hz. The subjects were more focused about listening to music and more generally satisfied after the sessions in which they listened to 432 Hz tuned music.Conclusions
The data suggests that 432 Hz tuned music can decrease heart rate more than 440 Hz tuned music. The study results suggest repeating the experiment with a larger sample pool and introducing randomized controlled trials covering more clinical parameters.
IntroductionMusic has always been perceived as having special healing powers in people. The whole history of human civilization shows evidence of connections between music and physical and mental healing.1,2From the point of view of physics, music is made up of sounds that are generated by waveforms whose frequency is expressed in Hertz (Hz). The Hz express the cycles per second (1 Hz = 1 cycle per second).3Specifically, the frequency values determine the tonality and influence the timbre of the sounds.4The current reference frequency for tuning musical instruments is 440 Hz, which corresponds to the musical note A4 (LA3) in the central octave of the piano.4 This frequency value was established in the 1950s5 and confirmed in 1975 as the standard tuning for music worldwide.6
So, nowadays, all the music we generally listen to is tuned to the 440 Hz frequency.4
The 432 Hz tuning is sometimes used in the New Age genre (meditation music)4 and by some musicians. Furthermore, on the web (YouTube) there are music tracks that have been transposed to 432 Hz from their original 440 Hz tuning.The transposition of music from 440 Hz to 432 Hz is obtained by imperceptibly slowing down (by 32 hundredths of a tone) the execution of a song originally tuned at 440 Hz, using music editing software.7 The transposition process can also be viewed in different videos on the web (YouTube).
The frequency of 432 Hz music, as already mentioned for 440 Hz, refers to the value of the note A4 (LA3) of the central octave of the piano, which is taken as a reference to tune all the other notes in the time system.4Currently, musicians using 432 Hz, as well as opera singers in the 1980s, declare that when musical instruments are tuned to 432 Hz, music becomes “hotter” and the perceived volume seems higher at parity of Decibel (dB).5,8Italian opera singers in 1988 proposed to modify the tuning-fork for tuning the orchestras of the opera houses to 432 Hz, and the composer Giuseppe Verdi had already requested this in 1884; his request was granted in a decree which, however, was never applied.5,9
In fact, in 1989, in line with the 1975 European directives, the A was also legally fixed in Italy at 440 Hz.10Maria Renold explains in her book describing some experiments,11 that when listening to a piano concert with a standard pitch based on a 440 Hz LA, the listeners present in the room during the performance assumed polemic, aggressive behaviors.
When the tone of the same instrument was brought to 432 Hz, the same people, once again invited to listen to the same concert, perceived the music as being better, and showed much more attention in listening.Renold has described these behaviors for over twenty years, interviewing and testing the two different frequencies on more than two thousand people.11In an article by the Schiller Institute12 it was stated that the most scientifically correct tuning is 432 Hz.13 This article explains the mathematical calculations by which this conclusion was arrived at, referring to historical figures such as Leonardo da Vinci, Johannes Kepler and Leonardo Pisano (known as Fibonacci).13NASA (National Aeronautics and Space Administration) shows us in real time that the terrestrial frequency is about 8 Hz (“Schumann resonance”).14 This would therefore be in mathematical relation with 432 Hz, since 8 Hz is a submultiple of 432 Hz for the ratio between frequency and octave music.In fact, it can be calculated starting from the octave of the A4 = 432 Hz in which the C4 (DO3) corresponds to 256 Hz. The following is the mathematical relation: 256/2 = 128 Hz (C3); 128/2 = 64 Hz (C2); 64/2 = 32 Hz (C1); 32/2 = 16 Hz (C0); 16/2 = 8 Hz (C-1).4 This same mathematical relationship does not exist in 440 Hz because the C4 (DO3) corresponds to 261.63 Hz.4
Because of this harmonic misalignment, listening to 440 Hz music would seem to make people anxious, nervous, or aggressive, because it is not in harmony with the natural frequency of the planet earth.These same effects would have repercussions on human health since our DNA is sensitive to frequencies, as stated by the Professor Carlo Ventura's team.15Human DNA is sensitive to music and its relative frequencies to the point that it can even be reprogrammed through them. In fact, by subjecting stem cells to various frequencies it has been possible to modify their natural organic function.15
There are several publications on the web16,17,18 and some books,5,11,19 but there are no scientific publications on the presumed benefits of tuning at 432 Hz.It seems that the benefits of music tuned at 432 Hz are not related to the musical genre (classical, jazz, rock, pop, etc.), but exclusively to the frequency and relative tonalities of the music.4Di Nasso et al.’s study suggests that music tuned to 432 Hz can be used as a remedy for anxiety and pain in dental treatment. However, the effects of listening to music tuned to 432 Hz have not been compared to the effects of listening to music tuned to 440 Hz in this context.20Any type of music could be produced at and/or transposed to frequencies of 432 Hz with specific music editing software.7
In the complete absence of scientific evidence regarding the beneficial effects hypothesized by listening to tracks recorded at 432 Hz compared to the 440 Hz standard, a pilot study was designed to identify the effects and possible differences between the two frequencies on human vital parameters.Furthermore, the perceptions of the subjects were explored during and after listening to music recorded at the two different frequencies, together with the general level of appreciation of the listening experience.
Section snippetsStudy design, sample selection and implementation settingA double-blind crossover study was performed, with a convenience sampling. Subjects were recruited by voluntary responses, via social networks (Facebook and Twitter). Subjects who chose to participate were divided into two groups (Group A and Group B) to facilitate their involvement in the investigation. The study was performed in a listening room provided by the municipal authority of Certaldo (Tuscany, Italy). The electronic equipment used consisted of a portable Digital Audio WorkstationGeneral characteristics of the sample
36 subjects participated in the survey, but 3 of these left the study after the first listening experience and did not show up for the second listening experience (drop-out). So, the data analysis included 33 subjects, divided into 21 men (63.6%) and 12 women, who did not suffer from any disability and were apparently healthy. The average age of the sample was 45 (SD ± 17.4). 21 subjects were part of the first group and 12 subjects were part of the second one (the 3 subjects who dropped outDiscussion
In our pilot study with movie soundtracks, after the listening session with the music tuned at 432 Hz, we observed a significant reduction of the HR (5 bpm) and the RR (1 r.a.), with a slight reduction of both systolic and diastolic BP. No variation was recorded in the Oxygen Saturation, all participants breathed in ambient air (Fi O2 0.21%).There was no alteration observed in RR and in Oxygen Saturation during the hearing of music tuned at 440 Hz. With music tuned at 440 Hz, a significantConclusion
The results from the study suggest some potential beneficial effects from listening to music tuned at 432 Hz compared to music tuned at 440 Hz, opening a new perspective on the opportunity of listening to it daily and to having musical and electronic instruments exclusively tuned at this frequency instead of the current 440 Hz standard, that has only been standardized since the 1950s. It is logical to think that standardizing to a single tuning is more practical, so we hope that similarAcknowledgements
We thank Tiziana Nannelli - PhD and Elisa Benedetti - RN for the support in carrying out the study.We thank the municipality of Certaldo (FI, Italy) for the use of room where we conducted the study.