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EverTones

       iOS iPhone

EverTones is a sound toy that brings a very cool auditory illusion to your iPhone or iPod Touch.

This application lets you play either a single tone or series of notes that endlessly increase or decrease in pitch but never ultimately end up any higher or lower, no matter how long you listen.

This illusion is sometimes referred to as an audio barber pole since the sonic effect is similar to the behavior of the white and red spiral stripes that seem to keep climbing upward as a barber pole spins. People have also referred to it as the audio equivalent of M. C. Escher's lithograph "Ascending and Descending" which depicts a never ending staircase.

The effect was described by Bell Labs psychologist Roger Shepard in a 1964 paper entitled "Circularity in Judgements of Relative Pitch" which was published in the Journal of the Acoustical Society of America.

A version of the effect has been identified in numerous musical works including Pink Floyd's Echoes, Queen's A Day at the Races, Robert Wyatt's Rock Bottom, Bach's Fantasy and Fugue in G minor for organ, and Chopin's Etude no. 3, op. 10 as well as in the sound of the Bat-Pod in the Batman film, The Dark Knight.

Lots of fun and a great conversation piece!

A great choice for those who enjoy audio / sound oriented entertainment and utility apps like Sound Grenade, Sound Grenade Pro, Ambiance, or White Noise.

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Last changed:

Feb 19, 2009

Category:

Entertainment

Developer:

Shifting Blue

Version:

1.0

Average Rating:

2.50 (25)

Size:

31.2 MB

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