01273 930040

100v Line Background Music Systems

What is a 100v Line Background Music / Paging Tanoy System

100v line systems are designed for commercial sound projects such as restaurants, shops, factories show rooms and offices where lots of speakers are required at various points around the area.

100 Volt Line (100v line) speaker systems is the most efficient way to install a multi-speaker sound system. These are often referred to as a Tannoy  system and making announcements  is often called paging.

The term 100V system relates to the maximum output voltage of the amplifier. To generate this high voltage the amplifier is equipped with a step-up transformer, which increases the normal output voltage of around 30 Volts, up to 100 Volts.

Zones - Areas

How to install and Setup

100v Line Speakers

100v line speakers can be ‘daisy chained’ from one to another over long distances with no variation in the mono sound from each speaker. 100v line speakers are fitted with a transformer which has ‘tapings’ on the back which allows the user to select the wattage. Changing the wattage will increase or decrease the maximum volume from each speaker; this allows complete control over different sound sensitive areas.

The Big difference between a low-impedance speaker system (4 or 8 Ohms) is the way the individual loudspeakers are connected to the amplifier, with a low-impedance system care has to be taken to maintain the correct impedance for the amplifier.

Parallel connection of 100V Line Speakers – ‘Daisy Chained’

In a 100V line system, a large number of single loudspeakers each equipped with a step-down transformer can be connected to one single speaker cable. With the 100V line installation, each speaker or speaker cabinet is equipped with a step-down transformer.

100v line speakers are available in many formats such as wall mount, ceiling speakers, corner or Cluster. Some hang from ceilings as Pendant above workshops or garage areas.

Speaker Cable

The amplifier power limits the number of speakers that can be run on any 100v line system. When installing a 100V line system, it is important that the correct size of cable is used

First decided how many speakers will be required and calculate their total wattage by adding together all the used tapping values.

Use the table below to calculate the correct cable size.

Cable Size
  0.75mm² 1.0mm² 1.5mm² 2.5mm² 4.0mm² 6.0mm²
30 Watt   800m  1066m  1600m  2666m  4266m  6400m
 60 Watt  400m  533m  800m  1333m  2133m  3200m
 120 Watt  200m   266m  400m  666m  1066m  1600m
 240 Watt  100m  133m   200m  333m  533m  800m

Simple 4 - 25 Speaker 100v Background Music System

This is a typical small system used in shops, restaurants and show rooms. The amplifier is 60W so if the speakers are tapped at 2W up to 25 speakers can be used and stay well within the capability of the amplifier.


Ceiling Speakers:

Speakers are measured by their driver dimensions so the overall size will be a little larger ( dimensions in link), 100v ceiling speakers have tapping’s on to set the volume of each speaker ( very simple, on the speakers below just connect to the appropriate connection/ coloured wire.) you will need around 2W per speaker as its only background.  For mounting of these speakers see rear image of spring clips which open up behind the tile.




You may also need a fire dome to cover the speaker to meet the building fire regulations. These fit over the rear of the speaker, see image in link.




A 100v line amplifier is designed for installation projects like this.

A small budget 100v amplifier with a single input.



A slightly larger amplifier but has more inputs so you could connect an iPod etc. But you would need access to the amplifier to change between sources, iPod tuner etc.




A professional tuner designed for this purpose.



Connecting it all together:

The speakers are all connected in parallel ( like a giant ladder) back to the 100v terminals on the amplifier using 100v speaker cable.



The tuner can be connected to the amplifier using a phono cable such as



If you wanted a iPod connection you could use a cable such as




If you wanted to mount all the equipment above the ceiling you could use a single volume control on a wall somewhere accessible. These volume controls connect in the speaker cable between the amplifier and the first speaker. They fit into a standard single gang back box so may be flush mounted.


back box for above.