What is 100V line audio?

HowToAV.tv explains 100v Line Audio - the most commonly used distributed sound system for commercial installations, public address and background music.

Purchase Amplifiers for 100v line audio systems at CIE Group100v line audio offers a simple solution for multiple loudspeaker / multi-zone sound systems distributed over long distances - such as large scale buildings, multi-floor and campus sites.

100 volt line is sometimes also referred to in the professional AV industry as 'constant voltage' or a 'high impedance' system. Using 100v line simplifies the installation of multiple speakers and allows the audio to be sent over longer distances with smaller gauge cable when compared with low impedance music amplifiers used in hi-fi or foreground/live music systems.

100v PA systems require specific 100v amplifiers and PA loudspeakers which feature a transformer - all of which are readily available from all professional audio distributors. These systems easily integrate with all standard audio source devices such as microphones, CD players, MP3 players and digital streaming systems.

100v line / PA / public address / BGM systems are most commonly applied to voice and background music applications, as opposed to foreground music and live performance. When you hear a paging announcement for example at an airport or railway station it will probably be through a 100v line audio system.

What amplifier should I use for my 100v line audio system?

  • Choosing the right amplifier for your 100v line audio system depends on the number of audio inputs you need as each audio source requires it's own input.
  • Once you have established the number of audio inputs needed, you then need to choose the amount and type of speakers that you want to install. Speakers often have a choice of power settings to choose from, these are called taps or tappings.
  • Choose which tappings is appropriate for the job - the higher the tap the louder the sound from the speaker. It makes sense to use the lowest tap for your installation. An example of this - A speaker has 6watt, 3watt and 1.5watt tap, you can have twice as many speakers on 3watt tap in comparison to if you used the 6watt tap on all your speakers. Click to find out more about 100v line tappings.
  • You can combine different types and power ratings of speakers dependent on the room size, sound levels needed and the environment it is installed into. Add up the wattage of the speakers and pick an amplifier that exceeds the load of the speakers and has the number of audio inputs you need.

Wiring up the speakers

When it comes to wiring up the speakers they can all be parallel and 'daisy chained' together without worrying about the impedance of the system. There is no messing around with series and parallel wiring to match the amplifier on a 100 volt line system. You can go speaker to speaker or even star wire from a central point. The only golden rule is the combined speaker wattage of all speakers should not exceed the output wattage of the amplifier.


100v line support from CIE GroupCIE AV Solutions - the UK's leading 100v line supplier

CIE AV Solutions is the UK's leading trade distributor of professional 100v line audio products and sound systems. With over 50 years experience in supply and system design for many of the UK's largest, high profile audio projects, our AV experts provide a unique level of technical support and customer service.
Call the CIE AV experts now on T. 0115 9770075 or email us at info@cie-group.com


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