Tag: YouTube

Shepard Scale

The Shepard scale is an auditory illusion of a tone that continually ascends or descends in pitch seemingly forever. The illusion can be created by overlapping ascending or descending scales.

It’s sometimes used in music, such as at the end of this song:

Gabor Patches — Creating Fascinating Optical Illusions

gaborMan, I used to think optical illusions were the simple, “which line is longer” sort. But I have seen some optical illusions in the past decade or so that have really caused me pause. It’s like there’s been some sort of optical illusion renaissance recently.

Here is one of the animated variety that wouldn’t have worked presented, as they were when I was young, in book form. Wow.

Okay, I was curious, what is a “gabor element”? It turns out the “Gabor filter” has an interesting mathematical (and even biological) origin.

For the creative, there is a nice online tool allowing you to create a gabor element here. It should be possible to generate a series of them out of phase and stack them with a GIF-creation tool in order to experiment with you own illusions similar to the above.

Dies Irae

Dies Iræ is a Latin hymn describing the day of judgement. The first line is as follows:

Dies iræ, dies illa

Since used in the hymn, the first few notes of Dies Iræ have appeared in a lot of music, especially movie soundtracks, from The Nightmare Before Christmas to It’s a Wonderful Life to Star Wars: A New Hope. Once you hear it, you’ll start noticing it everywhere. This video gives a history of Dies Iræ, from classical music to modern movie soundtracks.




If you’ve ever had someone brush your hair and felt tingles down your scalp, that’s ASMR. It stands for Autonomous Sensory Meridian Response, but most just know it as tingles and a relaxed feeling. ASMR is usually triggered by stimuli such as whispering, crinkling, tapping, or “squishing” noises, personal attention, and mouth noises. (I find it strange that I usually find mouth noises very irritating, but relaxing in the context of an ASMR video.) There are many more triggers, and many YouTube videos dedicated to stimulating ASMR through these triggers. Whispering is the most common trigger, and before ASMR was well-known the videos were known as “whisper videos”. Today, ASMR is much less obscure, but the ASMR community is still known as being part of the “weird side of YouTube” and there continue to be misconceptions about the sensation. For example, the scalp tingles associated with ASMR are sometimes colloquially called a “head orgasm”, and many outside of the ASMR community falsely perceive the phenomenon as being sexual in nature.

Many people will point to Bob Ross’s The Joy of Painting videos as their first experience with ASMR. It’s not hard to see why, with Bob Ross’s quiet, relaxing voice and the gentle sounds of the paintbrush on the canvas. I can’t pinpoint my first ASMR experience, but all my life I’ve found getting my hair brushed and played with to be very relaxing and tingle-inducing. Not everyone is able to experience ASMR, but even if they don’t feel tingles many people still find the videos very relaxing. However, with so many triggers, many people can find something that will give them tingles.

ASMR parody video by CollegeHumor:

The Automobile Transmission

Especially with the popularity of cars with automatic transmissions, many drivers today may forget that there are complicated systems of gears that transmit power from the car’s engine to the car’s wheels. Drivers that can work a clutch and a stick shift are certainly aware of a cars gearing but may be clueless as to how it all goes together.

An educational film from 1936 shows how an automobile’s gearing is put together.

When the film begins, it describes the lever and its mechanical advantage. Soon however the subject turns to gears and the modern (for 1936) automotive transmission.

The gearbox they detail, which was standard at that time, is merely a three speed transmission (plus reverse) and yet it is already fairly complex. It boggles the mind what a modern seven speed gearbox must resemble.

I don’t believe it is the case any longer that public schools offer vocational classes. I remember in middle school (junior high) I took a wood shop class. I enjoyed that experience a great deal. They offered metal shop and automotive shop classes as well.

I imagine the following film might have been shown in an automotive class. It’s wonderful how it describes the problem and then the solution that differential gearing provides in a way most students can probably understand.

An educational look at how things work. More films like this, please.
(The actual education content begins about 1:55 into the film.)

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