Before we get into the difference numerically, let’s first talk about what this word Hertz has to do with music. When you hear a sound, let’s say a refrigerator buzzing, you are experiencing the vibrations or frequency of the refrigerator’s motor traveling through the air to your eardrum and vibrating off the bones in your ear. This vibration or frequency is measured in Hz. For sound, this means the number of pressure waves per second that would move past a fixed point. It is also the same as the number of vibrations per second the particles are making as they transmit the sound. A sound of 20Hz means that 20 waves would pass a fixed point in 1 second, that would be a very low pitch. As humans, we can hear from around 20hHz to 20 kHz (2,000 Hz).
The musical world starting in the 18th century used the note A4 as the main tuning note for everyone in the orchestra, mainly because it is an open string on both the violin and viola. This particular A on the piano is the A above middle C. The diagram below is an 88 key piano. Middle C or what is called C4 is highlighted in teal and just above that (to the right) is A4 highlighted in yellow. The number next to the note I.E. A(4) means it falls into the 4th octave on the piano shown by those brackets in the diagram below. Octaves 0 and 8 are obviously incomplete. Octaves contain twelve half notes or semi-tones. Count all the white and black keys within one bracket and you get 12 half steps or semi tones, which makes up an octave. Octaves also start and end on the same note, an octave above or below.
Are you still with me? Ok, so now that we know where A4 lies on the piano, we can talk about its journey through time and why it ended up where it is now at A440 Hz.
Before 1953 there was no standard reference point for the frequency of A4. It differed for each country and each orchestra.This made it hard for musicians traveling to adapt, with their p articular instruments being tuned and built for their set frequency range. For example, before 1953 France used 435Hz as their point of reference for A4. In 1953 The International Organization for Standardization met in Stockholm and created 440Hz to be the reference point for all nations. Many prominent orchestras still wave their freak flag and don’t conform. For example, the New York Philharmonic uses 442, while many symphonies in parts of Europe use 443 or 444. When you are tuning by cents you may not even hear the difference, it’s more of a feel. It’s interesting to note that modern orchestras that specialize in playing ancient music, will use instruments made to specifications of that time period, and use what they think was the prevalent tuning reference also. From Renaissance music at 466Hz to French Baroque at 392Hz, there is a wide range that we can use today outside of 440 to bring about a different feel in the music.
Let’s now talk about 432Hz and where this “magical” tuning came from? From what I have gleaned from many sound healing related websites, there is a common thread. Here are some quotes from them describing 432Hz. “Softer on the ears”, “creates inner peace”, “more relaxing”, “more harmonic and pleasant”, “releases emotional blockages”, you get the gist. To go back to the beginning, we need to talk about Joseph Sauveur. He was born in France in 1653 with a hearing and speech impediment. He was completely mute until the age of 7. He became a prominent mathematician and physicist who, in 1713, came up with the concept of a scientific or philosophical pitch. He was not a musician, but a scientist, looking for a perfect mathematical structure that would eliminate any decimals. His Sauveur pitch or Verdi tuning, is an absolute concert pitch standard which is based on middle C (C4) being set to 256 Hz rather than 261.62 Hz, making it approximately 37.6 cents lower than the common A440 pitch standard.
Here is a chart of the Sauveur pitch. Notice how each octave lands on an even integer with no decimals. Convenient, but where in nature is everything so perfect? My guess is he is a bit like me and he likes order. So with his pitch chart centered on C, A4 would end up at 430.54 Hz. Ok, close to 432 right?