Akustische Täuschungen/Acoustic illusions
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|Endlos ansteigende Melodien: Der Shepard-Effekt. Endlessly rising melodies: The Shepard effect. (Illustration: M. C. Escher: Treppauf, treppab - ascending, descending.) Besides the well-known optical illusions there are acoustic ones, too. Perhaps the most popular is the effect that was discovered by Shepard: A scale that gives the listener the impression of an endlessly rising melody - but in fact the pitch of the tones does not rise. This way it is possible to play musical pieces that would otherwise cross the human perception threshold. Demonstration of an endlessly rising scale on a vibraphone; J. S. Bach's canon per tonus.|
|Levels:||High School (9-12), College|
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