A cardioid (from the Greek καρδία "heart") is a plane curve traced by a point on the perimeter of a circle that is rolling around a fixed circle of the same radius.
In acoustics, the dummy head recording (also known as artificial head, Kunstkopf or Head and Torso Simulator) is a method of recording used to generate binaural recordings.
A Jecklin disk is a sound-absorbing disk placed between two microphones to create an acoustic "shadow" from one microphone to the other.
A microphone, colloquially nicknamed mic or mike, is a transducer that converts sound into an electrical signal.
The NOS stereo technique is a method of capturing stereo sound.
The Office de Radiodiffusion-Télévision Française (ORTF) was the national agency charged, between 1964 and 1974, with providing public radio and television in France.
Radio France is a French public service radio broadcaster.
Stereophonic sound or, more commonly, stereo, is a method of sound reproduction that creates an illusion of multi-directional audible perspective.