The Empire's new sound system installed in the early 1950's for reproducing sound from the film sound track was WESTREX - the trade name of Western Electric, an American based company.
For those who may be interested, the film sound track is shown by the black strip on the right illustration - on one side of the 35mm film. A light beam shone through the track, which was picked up by a photocell to convert the light fluctuations to sound via an amplifier.
The Western Electric sound amplifier is pictured on the right.
When commissioning the sound system, the recorded sound track of guns from the battle of El Alamein was used to test the speakers.
It is interesting to note that there was a buzzer signalling system between the hall and the projection room to raise or lower the sound - one buzz to turn it up and two to turn it down. This system was necessary because the sound varied with the number of people in the audience - as it does at home with a room with and without soft furnishings.
The Empire, like many other cinemas, were very proud of their sound systems and usually displayed a plaque in the foyer.