Visualizing Sound with the Ruben’s Tube

by Myya McGregory

Is it possible to visualize sound? The Rubens’ Tube invented in 1905 by Heinrich Ruben, a German physicist, might be able to help us answer this question.

Students of physics might be very familiar with this contraption, but for those that are not, it might be helpful to think of a gas grill burner. Just like a gas grill burner, a Rubens’ tube is just a tube with holes in it attached to gas tank. The only difference is the other side is attached to the speaker of a frequency generator.

The idea of being able to see sound is predicated on sound traveling in waves. Humans can only hear frequencies from approximately 12 hz to 20 hz. In addition to hearing the sounds, we can also feel the vibrations from these sounds.

Rubens’s Tube by Flickr member, Pete

The height of the flame is determined by Bernoulli’s Principle since pressure is equal throughout the tube. When sound waves travel through the tube combining with the pressure from the gas, flames peak at the antinodes of the sine wave. When the gas pressure is lowered the amplitude of the flames will be higher at the nodes.  Mythbusters explains it well.

Now that we have established that sound waves can be visualized, let’s have some fun with it!

Jared Ficklin takes the concept one step further in his most recent TED talk. He brings out a flame table and digital renderings to examine eigenmodes, the vibrational modes of oscillating systems. This way he can analyze the effects of more than one frequency and show the complexity of sound. He even created a rendering of Nirvana’s “Smells Like Teen Spirit”.

How do you visualize sound? Have you ever seen a sound wave? Share your stories below!

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The Herman Grid

Herman Grid

Don’t worry, you aren’t inebriated. Looking at the grid above you should see small sets of faint gray circles fading in and out of focus. A surface explanation of what is happening is a luminescence competition.

Instead of viewing the image above as intentionally distinct black grids, imagine it as sets of white horizontal and vertical lines placed on top of a black background. The combination of the background and foreground in the Herman Grid create what is called an equiluminant-weave. A weave is a class of stimuli consisting of intersecting vertical and horizontal bars. There are two types of weaves, a luminance-defined weave and an equiluminant-weave. A luminance-defined weave occurs when shapes and patterns of vertical and horizontal bars have different luminance levels. An equiluminant-weave occurs when shapes and patterns have equal luminance levels.  The grayish spots you see on the image result from light levels competing for your eyes’ focus between the horizontal white bars and black grids.

For more variations of the Herman Grid go to: http://www.schouppe.net/hello-world and click Flash-animation.

Hamburger, K., & Shapiro, A. G. (2007). The Hermann grid is an equiluminant weave [Abstract]. Journal of Vision, 7(9):236, 236a, http://journalofvision.org/7/9/236/, doi:10.1167/7.9.236.

How do our environments influence human cognition?

Much research has been devoted to “unaided” human cognition, that is neurological functions and processes that seem to operate independently of external devices (i.e. memory, perception, attention, etc.).  Less investigated is the ongoing interaction of humans with artifacts, and the influence that this active relationship with external objects has in the evolution of human learning and cognitive capacities.  We are immersed in a world that presents a myriad of active visual stimuli from video games, to computers, to television.  How do these devices and our habitual interaction with them shape our cognitive development?

This question is addressed in a study conducted by Jenn-Yeu Chen and Chun-Yu Chuang of the Institute of Cognitive Science in Taiwan.  The study’s participants consisted of two groups of fluent Chinese typists, one group proficient users of the zhuyin keyboard (a phonology-based typing system that prioritizes knowledge of a character’s onset consonant, medial vowel if one exists, the rhyme, and tone) and the other proficient cangje users (a typing system based on a character’s orthography, which requires the visual recognition of the two radicals that compose a Chinese character.)  The typists were presented with several tasks such as typing a short piece of text using their respective systems, going through a passage and pointing out a repeating, predesignated radical, and identifying the shared phonological characteristics of spoken characters.  The results of the experiments showed that zhuyin users  made primarily phonology-based errors while typing, passed over the predesignated character embedded throughout the passage with more frequency, and were more rapid in their response to the shared patterns of spoken words.  For each experiment, the opposite proved to be true of cangje users, who favored visual stimuli over phonological cues.  The findings suggest that the methodology of the zhuyin and cangje systems may shape the typists’ cognitive processes to demonstrate a bias for either a character’s phonology or its orthography, respectively.

The article (http://www.cogsci.rpi.edu/csjarchive/proceedings/2008/pdfs/p487.pdf) further illuminates the influence that our world has on our processes of perception and cognition.