Voice operated switch
Encyclopedia
In telecommunications, a voice operated switch, also known as VOX or Voice Operated eXchange, is a switch that operates when sound over a certain threshold is detected. It is usually used to turn on a transmitter or recorder when someone speaks and turn it off when they stop speaking. It is used instead of a push-to-talk button on transmitters or to save storage space on recording devices. On cell phones, it is used to save battery
life. On Intercom Systems that use a speaker in a room as both a speaker and a Mic will often use VOX on the main console to switch the audio direction when a conversation is going on. The circuitry usually includes a delay that leaves the circuit activated for a short time after the sound stops. This keeps the circuit from turning off during short pauses in speech.
There are pros and cons to choosing VOX as opposed to other methods as a triggering device. In recordings, the first second or so of information may be lost because the noise level must be checked before the recording is initiated. Ambient noise may also trigger recording of unwanted background noise. Cell phones, two way radios, phone recorders, and tape recorders often have VOX as an option.
In audio recording and sound reinforcement, the term 'vox' may be used as an abbreviation for 'voice', 'vocal track', or 'vocal channel', primarily because it is the nominative case of "voice" in Latin
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A special case exists, if there is enough energy to power the system directly. For example, a microphone may spend a voltage, high enough, to directly operate a transmitter.
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
life. On Intercom Systems that use a speaker in a room as both a speaker and a Mic will often use VOX on the main console to switch the audio direction when a conversation is going on. The circuitry usually includes a delay that leaves the circuit activated for a short time after the sound stops. This keeps the circuit from turning off during short pauses in speech.
There are pros and cons to choosing VOX as opposed to other methods as a triggering device. In recordings, the first second or so of information may be lost because the noise level must be checked before the recording is initiated. Ambient noise may also trigger recording of unwanted background noise. Cell phones, two way radios, phone recorders, and tape recorders often have VOX as an option.
In audio recording and sound reinforcement, the term 'vox' may be used as an abbreviation for 'voice', 'vocal track', or 'vocal channel', primarily because it is the nominative case of "voice" in Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
.
A special case exists, if there is enough energy to power the system directly. For example, a microphone may spend a voltage, high enough, to directly operate a transmitter.