Before I begin drawing connections between the two different concepts I have discussed more clearly, I just want to clarify that this is a very narrow view of how this phenomenon appears. The psychological aspects surrounding how people perceive sound and translate these into emotions are extensive. An article on the English edition of Wikipedia called “Music psychology”[1] shows how this field is an umbrella that covers a range of research areas, everything from performing music to listening. Music psychology is a field that strives to explain why human music sounds the way it does, and is rooted in how people perceive tonalities, soundscapes and other characteristics in musical works. What I will do in this post is unite the concepts of sound and tension, and then hold a hypothetical discussion about this regarding how people can perceive a sound as “tense” and why it affects us as it does.
Creating Sound
Looking at my post about the building blocks of sound, we can see how sound is vibrations that spread in a medium. What I haven’t discussed is how these vibrations arise. That is; for a sound to be created, a medium like air must be set into vibration, which can be accomplished in several ways. Humans have throughout their history developed instruments to create sound and shape music with these. In “The Physics of Musical Instruments” (N. H. Fletcher, T. D. Rossing; 1998) introductory chapter, different instruments are categorized according to how they create sound.
“Mechanical, acoustic, or electrical vibrations are the sources of sound in musical instruments. Some familiar examples are the vibrations of strings (violin, guitar, piano, etc.), rods or bars (xylophone, glockenspiel, chimes, clarinet reed), membranes (drum, banjo), plates or shells (cymbal, gong, bell), air in a tube (organ pipe, brass and woodwind instruments, marimba), and air in enclosed spaces (drum, violin, or a guitar body).
In most instruments, sound is created according to the combined properties of several vibration sources, which can interact with each other to varying degrees. [This is called ‘timbre’] This interaction can, together with nonlinear [acoustic] response, make the entire instrument itself behave as a complex vibrating system, even though the individual elements are relatively simple vibration sources.”
– The Physics of Musical Instruments” (N. H. Fletcher, T. D. Rossing; 1998) chapter 1 (my translation). [Translated from Swedish back to English again, may not reflect the original text]
This text explains where a sound can arise, and an interesting source of tension can be found in strings. A string is a length of elastic material that is attached between two points. When this is done, the string gets a so-called fundamental frequency. This frequency is determined by several factors that were first defined by the Renaissance man and musician Vincenzo Galilei. He claimed that a string’s fundamental frequency depends on the length of the string, its mass, and its linear density (i.e., extension, or tension). This can be seen in the following video, where the first example shows how a person sets all the strings on a guitar into vibration. We can see how the thicker strings vibrate with a lower frequency than those with less mass. The tension in the strings can also have an impact on their respective frequencies.
If any of the above-mentioned factors are changed in a string, it occurs with the following outcome.
- The length of the string: If the string is longer, it has a lower fundamental frequency; a shorter one has a higher fundamental frequency.
- The string’s mass: A string with higher mass has a lower fundamental frequency; one with less mass has a higher fundamental frequency.
- The string’s linear density (tension): A string that is more loosely tensioned has a lower fundamental frequency; one more tightly tensioned has a higher fundamental frequency.
The last point is very interesting as it begins to flirt with the idea that tension and sound have a direct connection to each other, and not just as a human conception of sound, but as a physical phenomenon that could explain why we can perceive how certain sounds sound more tense than others. If a human has ever experienced how a change in tension affects pitch, one can develop a perception that a sound with higher frequency comes from a source that is more tightly tensioned than a sound with lower frequency. A follow-up question we can ask ourselves then is: Is there a personal relationship to this phenomenon that all humans have?
In my first post about tension, I mention that people use the muscles around their vocal cords to express themselves with sound. The vocal cords function in such a way that when these are placed in the airstream that passes through the larynx, they begin to vibrate and therefore set the air into vibration. Humans can regulate the pitch in their voice by tensioning these vocal cords more strongly or more weakly. This is something that can be seen in the following video, where a pair of vocal cords are filmed while they change the voice’s pitch by tensioning up the vocal cords.
Perhaps it is the case that people associate a difference in raised pitch with an effort in muscle tension, so when a pitch increase is heard by a human, it is interpreted as something that becomes increasingly strenuous and laborious to listen to. Muscles can perform work for a certain time, but after too long work, muscles become tired and begin to require rest. Since people know that the implication of holding a tensed string in an even more tensed position is that it will become more difficult to maintain the tension.
We have now come to a point in the investigation where we can look for examples in works where pitch raising is used as a means to create tension in the listener and see if this is commonly occurring. We will either be able to reject this theory if we don’t find any examples, or confirm it. If we confirm the theory, we can also analyze these works further to find complementary components that are used to reinforce the feeling we have discussed.
This phenomenon that the post has dealt with – how people seem to associate the character in a sound with the character of its source; in this case tension – can be expressed with the designation “Phonetens” or “Phontension”. This is a combination of two words. ‘Phonetics’ (which derives from the Greek word phōnē which translates to ‘sound’ or ‘voice’), and despite this being a designation for a scientific area around the voice, it comes in handy in this case since ‘phon’ is used when in acoustics one explains that human perception of sound and its strength differs from the actual sound strength. The second word can be shortened from English ‘tension’ to ‘tens’, which is also used in Swedish as a synonym for ‘spänning’ (tension). Phonetens can be used as a collective name for sounds that represent tension, and going forward the investigation’s focus will lie more on applying this designation in different examples to create a clearer picture of what the expression can encompass.
Resource
1; Anonymous. (2013). Music psychology. Available: http://en.wikipedia.org/wiki/Music_psychology. Last accessed 28 oct 2013.
My name is Jacob Westberg and I am a game composer, software developer, and educator of game audio. You can find topics here surrounding creative work in game music that I find insightful and interesting to research.
In order to share my research with others for free, all articles on this website will be open and accessible for anyone. You can support this open research by subscribing to my Patreon.