Embedded Sound / Acousmatic / Electroacoustics
2 Examples of embedded sound on the Internet:
> David Toop – Oceans of Sound (MySpace), (Website)
> Amon Tobin – (Website Field Recording Excursion)
Steganography - mp3stego
The art and science of hiding information by embedding messages within other, seemingly harmless messages. Steganography works by replacing bits of useless or unused data in regular computer files (such as graphics, sound, text, HTML) with bits of different, invisible information. This hidden information can be plain text, cipher text, sound or images. Steganography is sometimes used when encryption is not permitted. Or, more commonly, steganography is used to supplement encryption. An encrypted file may still hide information using steganography, so even if the encrypted file is deciphered, the hidden message is not seen. Steganography (literally meaning covered writing) dates back to ancient Greece, where common practices consisted of etching messages in wooden tablets and covering them with wax, or tattooing a shaved messenger’s head, letting their hair grow back, then shaving it again when they arrived at their contact point. See source > http://www.webopedia.com/TERM/S/steganography.html
ACOUSMATIC ART & SOUND
See: http://www.acousmatic.com/
The term acousmatic dates back to Pythagoras; the philosopher who is believed to have tutored his students from behind a screen so as not to let his physical and visual presence distract them from the content of his lectures. It refers to the “perception of sounds of which we ignore the origin.”
Acousmatic art/music is a form of music which is presented through loudspeakers to an audience from an analog or digital source and may contain sounds that have recognisably musical sources, but may equally present recognisable sources that are beyond the bounds of traditional vocal and instrumental technology. You are as likely to hear the sounds of a dripping tap, or an animal as you are the sounds of a cello or percussion. The technology involved transcends the mere reproduction of sounds. Techniques of synthesis and sound processing are employed which may present you with sounds that are unfamiliar and that may defy clear source attribution. This form of music may present you with familiar musical events: chords, melodies and rhythms which are easily reconcilable with other forms of music, but may equally present you with events which cannot be classified within such a traditional taxonomy. Listen to 2 examples of Acousmatic music > Whispering > H2O (for Cello and 4 dripping taps)
In cinema, acousmatic sound is sound one hears without seeing an originating cause – an invisible sound source. Radio, Internet and telephone, all which transmit sounds without showing the source cause, are acousmatic media.
Offscreen sound in film is sound that is acousmatic, relative to what is shown in the shot. In a film an acousmatic situation can develop along two different scenarios: either a sound is visualised first, and subsequently acousmatized, or it is a acousmatic to start with, and is visualized only afterward (usually through the use of an L-cut or split edit, where the picture transition does not occur coincidentally with the audio transition).
• The first case associates a sound with a precise image from the outset. This image can then reappear in the audience’s mind each time the sound is heard off screen.
• The second case, common to moody mystery films, keeps the sound’s cause a secret before revealing all. (De-acousmatization).
The opposite of Acousmatic sound is Visualized sound – a sound accompanied by the sight of its source or cause. In film an onscreen sound whose source appears in the image, and belongs to the reality represented therein. (Edited excerpt: Michel Chion, Audio-Vision)
See source: Acousmatic Sound: http://filmsound.org/chion/acous.htm
See also links to Electroacoustics and Musique Concrète