What is perfect pitch? The ability to identify or recreate a musical note absolutely without a reference is called perfect pitch. The ability benefits musicians because they are able to sing in a particular key at will, transcribe melodies easily, and tune instruments to concert pitch without a tuner. Recognizing and recreating musical notes are slightly different skills but many people who have perfect pitch are good at both. Click here for more info: perfect pitch software.
Perfect Pitch Theory
The important question, which was never given enough attention until now, is not that of “what?” but the question of “how?”. We all know what perfect pitch is, but how do this minority of people recognize these supposed elusive “qualities” of the notes? How does the ability work and what are the “qualities” that people say separate the notes? Most people can perform quite amazing feats of aural recognition, such as recognizing the characteristics of many different friends’ voices and some great musicians do not have perfect pitch. So, how is it that we cannot all hear these note differences?
To answer these questions, we need to understand a few basic acoustic principles. To start with, tonal sounds from any source contain fundamental frequencies of the notes being played as well as harmonics of those frequencies. Harmonics are also called overtones and all tonal sounds contain them. Even the simplest sound wave will generate harmonics. Waves have a physical property that they create more waves. The harmonics of a tone are multiples of the fundamental frequency. The sound you hear when a single A440 note is played is a combination of 440 Hz, 880 Hz, 1320 Hz, 1760 Hz, 2200 Hz, and so on. Usually the fundamental (440 Hz) has the most energy, the second harmonic (880 Hz) has less, and the general trend is a decrease in volume as you count up the harmonics, although some instruments do take exception to this. Incidentally, the second harmonic is the same as the “first overtone”.. To avoid the confusion about this, I will use the harmonic terminology only.
The harmonic spectrum for each instrument is different. For example, a clarinet has a strong fundamental with stronger odd harmonics than the even ones. The guitar, on the other hand, has a higher second, sixth, and seventh harmonic.
Of course the spectra of different instruments differs. The instruments do not sound alike at all. It is the levels of the harmonics of tonal sound, which (along with components of noise) give the particular timbre to the sound. The variance in harmonic spectra allows us to easily tell the difference between instruments. Click here for more info: perfect pitch training.
In summary, the unique “quality” or timbre of a tonal sound is always determined by its harmonic levels.
Getting back to the subject of perfect pitch, we know that musicians who have perfect pitch hear differences in “quality”, we might even say timbre, between the notes. A composer may write a piece in F sharp if it is to be uplifting but will possibly choose E flat for a more sorrowful piece. So how does this fit in with the harmonic spectra of the notes when we know this to be determined by the instrument? Well, the shocking, but obvious truth is that there is no physical difference in ”timbre” between the different notes. In fact, if there were, we would have measured it decades ago and there would be no mystery surrounding perfect pitch. It is the human ear, which is responsible for perfect pitch, and the differences between notes are only perceived because of the resonances and frequency response of the ear.
Like a microphone, the human ear can hear some frequencies better than others and contains certain parts, which are able to resonate strongly at particular frequencies. Tonal sounds contain many frequencies and they will all affect the ear differently. We hear some frequency components as louder than others when they actually have the same loudness.
The response does not differ much between people and can be seen on a common Equal Loudness curve. The ear is most sensitive at 4000 Hz and a sound at 30 Hz has to be almost one million times as powerful as one at 4 kHz to be perceived the same.
A series of resonating components make for resonances in the ear. The Auditory canal has a resonance of 3000 Hz. Other sources for non-linearity in the ear are the complex cochlea behavior, the vibration of the eardrum, and the bones in the middle ear.
Of course, the equal loudness response of the ear is only part of the story of human hearing. The ear is always exposed to many different frequencies and there are many complex phenomena at work. One example is masking, when one frequency interacts with another, which is dependent on the values of the frequencies.
So What is Perfect Pitch?
In conclusion, perfect pitch is about the perceived spectra of the harmonics of the notes. There are physical harmonic levels of any tonal sound. On the other, there is an internal spectrum from the response of the ear. The brain is an extremely complex machine and those who have perfect pitch are simply able to tune in to the spectrum of the sound resulting from the resonances of the ear and can distinguish this from the physical spectrum created by the instrument. Musicians are, generally, much more concerned about the fundamental frequencies of the tones and less so with harmonics, which is why perfect pitch is so rare. To hear with perfect pitch, you need to be able to listen to the harmonics, which is a skill like any other and can be learned until it is second nature. For more info, click: what is perfect pitch?