ABSTRACT
This chapter describes the early days of sound in the cinema and also modern dubbing theatres. It explores the flawed concepts of room equalisation. The chapter discusses the improved methods of calibration and immersive audio systems. It was very much due to the demand for sound in the cinemas that the development of loudspeakers was so rapid in the 1920s and 1930s. The first 'talking picture' was released in 1927, yet this was only three years after Rice and Kellogg had patented the direct-radiating moving-coil loudspeaker, which was then only of a modest, domestic size. In the early 1970s, the advent of portable, real-time spectrum-analysers meant that, for the first time, cinemas could have their electro-acoustic responses measured and adjusted on site. In the 1970s, the cinema industry began investigations into room-to-room compatibility which later led to the standardisation of the 'X-curve' as the frequency response characteristic to which the soundtracks would be mixed and shown.
