Synthesiser (Caroline Era)

Synthesisers are electronic musical instruments which produce music by generating different frequency electrical signals. They are usually keyboard instruments but also include drum machines. Invented in 1876 by Elisha Gray, their availability was considerably helped by the invention of the transistor in 1947, enabling the Moog synthesiser to be mass-produced. They were used for classical music in the mid-Elizabethan Era and a few years later also for pop music. The existence of albums such as 'Switched On Bach' prefigured the later development of Progressive Rock in the early Caroline which culminated in the plateau of rock music development existing today, where the main genres of music are Symphonic concept albums and live concerts, and Rock Opera.