Archive for the ‘psychological’ Category
Former Disney audio experience engineer, Mr. Q, reveals how he assisted in developing a complex algorithm to arrange over 15,000 speakers around the Disney World theme park. All to achieve the ideal ambient music for “manufacturing emotion.”
The last time I visited Disney World, I was a bit distracted by the nausea that followed one too many rides after five too many scoops of ice cream. The visits before that though, I was entirely clearheaded. Yet not a single time did I notice the always present background music switch tunes.
Mr. Q would be laughing maniacally if he read those words. That’s because those words mean that his baby, the project he worked on in the 1990s, grew up to be a success.
Apparently the original Disney World speaker system, set up in 1968, had an unnoticeable flaw: minuscule variations in sound volume along pathways. As someone walked closer to a speaker, music would seem louder than a few steps away. Despite not a single visitor ever complaining about this common sound effect, twenty years later good ol’ Mickey decided to do something about it. Some work and a team effort later, they had Mr. Q’s system and algorithm:
The system he built can slowly change the style of the music across a distance without the visitor noticing. As a person walks from Tomorrowland to Fantasyland, for example, each of the hundreds of speakers slowly fades in different melodies at different frequencies so that at any point you can stop and enjoy a fully accurate piece of music, but by the time you walk 400 feet, the entire song has changed and no one has noticed.
So how is a system which strives to be unnoticed manufacturing emotion? According to Mr. Q, the “life is sucked out of” the park when the speakers fail. Even a slightly flawed speaker system could lead to frowns, while perfect music ambiance only leaves Goofy’s creepiness to achieve that.
The classification of noise by spectral density (power distribution in the frequency spectrum) is given “colour” terminology, with different types named after different colours, and is common in disciplines like acoustics, electrical engineering, and physics. The colour names are derived from a loose analogy between the spectrum of sound wave frequencies (as shown in the blue diagrams) and the equivalent spectrum of light wave frequencies. That means when the sound wave pattern of “blue noise” were translated into light waves, the resulting light would be blue, and so on. The Federal Standard 1037C Telecommunications Glossary defines white, pink, blue, and black.
White noise is a signal, named by analogy to white light, with equal energy per cycle (hertz). Just as white light is a combination of all the different coloured (frequencies) lights, white noise is a combination of all of the different frequencies of sound. This produces a flat frequency spectrum in linear space.
The frequency spectrum of pink noise is flat in logarithmic space; it has equal power in bands that are proportionally wide. The power density, compared with white noise, decreases by 3 dB per octave.
Many people describe white or pink noise as similar to running water, rain, or noise on a vacant TV channel. Most of the “sleep” machines on the market are based on generating variations of white or pink noise.
Blue noise is also called azure noise. Blue noise’s power density increases 3 dB per octave with increasing frequency over a finite frequency range. In computer graphics, the term “blue noise” is sometimes used more loosely as any noise with minimal low frequency components and no concentrated spikes in energy. This can be good noise for dithering; retinal cells are arranged in a blue-noise-like pattern for this reason.
Green noise is supposedly the background noise of the world. A really long term power spectrum averaged over several outdoor sites. Rather like pink noise with a hump added around 500 Hz.
Black noise has various associations. It has a frequency spectrum of predominantly zero power level over all frequencies except for a few narrow bands or spikes hence also referred to as silence. “The output of an active noise control system which cancels an existing noise, leaving the local environment noise free. Iron Man used to have a “black light beam” that could darken a room like this, and popular science fiction has a tendency to portray active noise control in this light.” The Batman Beyond supervillian Shriek also had a weapon like this, which effectively blocked out all noise.