Sunday, November 27, 2011

Good Vibrations: The Science of Sound

Source
http://worldsciencefestival.com/videos/good_vibrations_the_science_of_sound


World Science Festival – Good Vibrations: The Science of Sound

“We look around us—constantly. But how often do we listen around us? Sound is critically important to our bodies and brains, and to the wider natural world. In the womb, we hear before we see. John Schaefer, Jamshed Bharucha, Christopher Shera, the Danish sound artist Jacob Kirkegaard, and multi-instrumentalists Polygraph Lounge embark on a fascinating journey through the nature of sound. How we perceive it, how it acts upon us, and how it profoundly affects our well-being—including a demonstration of sounds produced by sources as varied as the human inner ear and the creation of the universe itself.”


Summary

The sound is the key to communication. Even before we can write, we communicated by sound. Sound is the glue that keeps everything together. The video explored various aspects of sound including the mechanics of our inner ears transmitting sound waves to our brains, the sound of the universe, as well as what kinds of sounds are perceived as music.


Each guest had his own expertise on the topic of “sound”:
Jamshed Bharucha – Cognitive Neuroscientist
Jacob Kirkegaard – Sound Artist
Christopher Shera – Auditory Physiologist
Mark Whittle – Astronomer
Polygraph Lounge – Musician / Performer


Sound and Physics
The basic fundamentals of sound are: pitch, loudness and quality. Pitch is the frequency in which the sound waves hit our ear drums. The higher number of wave, the higher the frequency, the higher the sound. Loudness refers to the amplitude of the waves (height measured from the highest and lowest points). The higher the amplitude means louder sound. A billionth difference in height equates to 15 decibels in sound, which is about a quiet conversation between two people side by side. The quality (timbre) of the sound depends on its fundamental and harmonics combined. Different instruments produce various configurations of harmonics, which is why two instruments playing the same note can sound different in quality. The second harmonic (2nd note after the fundamental) is made when the sound wave is directly cut in two halves, resulting twice the speed of vibration. This process makes an octave – which is an interval used in music of all cultures due to its natural quality. And because of the mathematical calculations of the harmonics, some ratios were used to tune instruments. This was also used to explain why consonances that follow those favourable integer ratios sound “nicer” than dissonances.


Sound and Speech
In a study where pitches were coded, the emotion of “sadness” had a descending minor 3rd speech pattern while “anger” had an ascending minor 2nd or an augmented 4th. On the other hand, the positive emotions such as “happiness” and “excitement” did not have any pitch codes at all. This was theorized that pitches in speeches were vital evolutionarily because negative emotions had to be communicated accurately. There were consequences for “anger” and “sadness”, and specific pitch patterns were formed to emphasize the specific emotions. This was seen in other languages as well. The auditory neurologist explained that when people are said to have accents, it is really just different musical patterns in their speech.


Sound and the Universe
The sound of the Universe are studied and made into music that we can understand today. Sound waves can be captured and analyzed, and mapped out according to the frequencies. The deeper and lower frequencies reflected denser atoms in the galaxy, and as time went on and on (and as the Universe expanded), the sound waves of the stars were stretched wider and wider. Hence the recording of the “history of the Universe” started with a high-pitched wail and slower descended into the lower registers. When all the frequencies were matched to that of a piano, the “chord” that represented the Universe was said to have a major/minor 3rd quality.


What makes it Music?
Some sounds we call music, and others we ignore as noise. We find some intervals favourable – such as the octave, as mentioned above – due to the nature of how they are made. We often say that music is a universal language, and the neurologist argued otherwise. A lot of what we prefer as “good music” are culturally learned and influenced. Wolves howl in packs as a form of social cohesion. They vary in pitch and duration, and could very well be music. There are sounds of nature all around us and it is how we perceive those surroundings that make them music.



Reflection

This is a video that I really enjoyed. It explored a lot of different ideas of sound, music and science. Things such as the sound of the Universe and the division of music versus noise are fascinating. The physics behind the fundamentals and harmonics gave insights to why certain instruments are tuned the way they are. Since music and math are so closely related, it is easy to see how things that fit in the math equation (such as the octave being the 2nd harmonic) sound more natural in music.


The findings regarding pitch patterns in speech was the most interesting. It’s remarkable how intervals of certain qualities (tritone – augmented 4th) are associated with certain emotions in speech. The research was done in different languages, so there must be an innate relationship between speech and music, and how our brains use these “sounds” to express language.


The sound of the Universe has never crossed my mind. It’s always easy to forget that music is just sound, and sound can be analyzed by each wavelength. It is then modified and made into music that we can understand today. Polygraph Lounge did a wonderful job and illustrating how anything can be made into music. Sometimes we are so caught up with music performance, teaching and learning that we forget that we are constantly surrounded by it. As the sound artist said, even our own ears make music. I think it’s important for music teachers – especially private instrumental ones – to explore the creative side of music-making. We can play on our instruments and learn about Beethoven and Opera, but we should also submerge ourselves into the sounds that surround us.

3 comments:

Katie said...

This post reminds me of when I was teaching my Grade 8 instrumental music class earlier this term. We always start each class with a discussion about music and the question I asked this time was “What is music?” Many started giving answers that included the elements of music and a few even started talking about environmental sounds. Soon a debate ensued about whether birdsong was considered music as well as precipitation and other natural phenomenon. We came to a consensus that music could be defined as “organized sound” in the context of our classroom, but outside the classroom it was determined on meaning, interpretation, and intent. So yes, “music” exists all around us, but we are the ones who ascribe meaning to it when we hear it and analyze it.
We really didn’t get much past the idea of environmental sounds in that class but we did have a similar discussion in my primary music class. When I asked students to describe what music they heard on the way to school in the morning, a few of them talked about the radio in the car or the t.v. before they left the house, but a lot of them talked about the sound of their shoes on the pavement or the swish of the wiper blades on the bus. I think as we get older our concept of “music” narrows based on our enculturation. We develop a hierarchy of sound based on what we experience as children.
I wonder if this holds true for the way our brain processes the visual aspects of making music. Would children consider watching a bucket-drumming ensemble less “musical” then watching an orchestral performance? And would these perceptions change as they aged?

Chairat said...

I am fascinated by the fact that the tritone and the ascending minor second are associated with the speech pattern for anger. Of course, the fancy name for the tritone is “Diabolus in Musica” (“The Devil in Music”) and I very much suspect that this name is no mere coincidence. As for the ascending minor second, I am reminded of the lighting-fast modulations of Schubert’s late works; in particular, the striking modulation from E major to F minor in the middle section of the second movement of his String Quintet in C major, D. 956 . This modulation sends shivers down my spine. I do not perceive it as just being dramatic, but rather, as is often the case in late Schubert, there is an underlying current of something infinitely more sinister and menacing. And I believe that it may have a lot to do with the ascending minor second modulation. I would be interested to find out if the music of other cultures also reflects these speech patterns.

Musical tastes may be culturally learned, but I think that one should also make the effort to actively listen to the music of other cultures as well. From my own experience, I have come to the conclusion that my brain tends to be pretty lazy most of the time. It likes to experience things that are familiar and predictable. Certainly, this is why one is more perceptive and skillful when it comes to listening to/performing music that one was exposed to from an early age. At the same time, however, there may be great value in listening to unfamiliar music, as this broadens one’s horizons and allows one to develop a new perspective on music that is familiar as well.

mrmusic said...

Stephen Chatman has written a choral work called "Thou Whose Harmony is the Music of the Spheres"
It is a fabulous choral work for SATB choir and solo oboe.

I thoroughly enjoyed this 1 hour exploration of the origins of sound. Having used the choral work above, I was intrigued by the explanation of sound (music) and how it has played an integral role in this amazing experiment called creation.