Browse Definitions :
Definition

silence machine or Electronic Controlled Acoustic Shadow System (ECASS)

The Electronic Controlled Acoustic Shadow System (ECASS), called the silence machine by its creator Selwyn Wright, an engineer at the University of Huddersfield in Yorkshire, UK, is the first device capable of blocking out a specified noise while leaving everything else audible. The silence machine works by sending out sound wave s that are the opposite of those being generated by the offending noise source.

Wright's sytem uses microphones to sample sounds and signal processors to measure the frequency of each part of the noise signal. A software application is used to create a noise that is the same frequency, but opposite in terms of phase . Each valley in the electronic opposite (sometimes called the anti-sound or the anti-noise ) meets a peak in the specified sound wave, and vice versa, so that the original sound is neutralized. Wright calls these areas where the sound waves cancel each other out sound shadows . The size of the shadow areas where the sound and anti-sound waves cancel each other out can be varied by changing the number (or position) of loudspeakers broadcasting the anti-sound.

The first version of Wright's machine is optimized for neutralizing continuous noise with predictable patterns, such as that generated by loud machinery. Silence machines capable of blocking other types of sound, such as music, snoring, and human speech, are expected to be available next year.

The concept of a silence machine was introduced in Arthur C. Clarke's 1957 short story, "Silence Please". Clarke intended it as a humorously improbable device - with dire consequences for the inventor.

This was last updated in March 2011
SearchCompliance
  • OPSEC (operations security)

    OPSEC (operations security) is a security and risk management process and strategy that classifies information, then determines ...

  • smart contract

    A smart contract is a decentralized application that executes business logic in response to events.

  • compliance risk

    Compliance risk is an organization's potential exposure to legal penalties, financial forfeiture and material loss, resulting ...

SearchSecurity
  • threat modeling

    Threat modeling is a procedure for optimizing application, system or business process security by identifying objectives and ...

  • distributed denial-of-service (DDoS) attack

    A distributed denial-of-service (DDoS) attack is one in which multiple compromised computer systems attack a target, such as a ...

  • social engineering

    Social engineering is an attack vector that relies heavily on human interaction and often involves manipulating people into ...

SearchHealthIT
SearchDisasterRecovery
  • change control

    Change control is a systematic approach to managing all changes made to a product or system.

  • disaster recovery (DR)

    Disaster recovery (DR) is an organization's ability to respond to and recover from an event that affects business operations.

  • risk mitigation

    Risk mitigation is a strategy to prepare for and lessen the effects of threats faced by a business.

SearchStorage
  • bare-metal cloud

    Bare-metal cloud is a public cloud service that offers dedicated hardware resources without any installed operating systems or ...

  • race condition

    A race condition is an undesirable situation that occurs when a device or system attempts to perform two or more operations at ...

  • storage security

    Storage security is the group of parameters and settings that make storage resources available to authorized users and trusted ...

Close