How electronics can be used to alter and/or create musical signals is considered. Emphasis is on those techniques where physics is evident, recognizing that much is now done using programming languages. Basic effects done using simple physics include distortion, reverberation, and tremolo. Various signal-processing and playback techniques are also used, along with psychoacoustics, to provide surround sound and other effects. Electronic music can be created using the Hammond organ, a theremin, and electronic synthesizers. A basic synthesizer will combine a carrier tone and a time-dependent amplitude for that tone in order to create different sounds. Although synthesizers are often controlled by keyboards, other user interfaces have also been developed that, for example, resemble a drum kit or a woodwind instrument.

The chapter considers the musical project Popol Vuh in the context of its special relationship to spirituality. Although referred to as a band, Popol Vuh consisted of pianist/keyboardist Florian Fricke and various co-musicians with whom Fricke attempted to express his spirituality through music. The chapter begins with an overview of Fricke‘s early creative phase, beginning with his first album Affenstunde, which, like the first side of its successor In den Gärten Pharaos, was still dominated by the sound of the Moog. A special focus is placed on the process leading Fricke to turn away from electronic music; opting for a sound as natural as possible, he hoped to find spiritual fulfilment in organic sounds. As the chapter discusses, Fricke‘s spirituality originated in the study of Eastern religious texts, which he combined with his own interpretation of Catholicism, for example on Hosianna Mantra. Finally, the use of Popol Vuh‘s music in the films of German director Werner Herzog is explored to explain how the two artists were able to achieve a unique synergistic effect in these films.