Glossary – O
1. A pitch interval of 2 to 1. 2. The tone whose frequency is twice that of the given tone.
Not directly in front (of a microphone or loudspeaker, for example).
In a microphone, a deterioration in frequency response of sounds arriving from off-axis locations. In a loudspeaker, a deterioration in perceived frequency response when the listener is standing off-axis.
The unit of electrical resistance, defined as a unitary voltage/current ratio. The higher the temperature of a substance, the greater the resistance. Resistance depends upon length, area and material used in a wire. A copper wire 0.1 inch diameter and 1,000 ft long has a resistance of l Ohm.
Fundamental generalization describing the flow of direct current in an electrical circuit, by stating that the magnitude of the current is proportional to the potential difference, provided the resistance is constant. (The unit of potential difference, the volt, has been so chosen that 1 volt is produced across a resistance of 1 ohm when 1 ampere is flowing through it
Equally sensitive in all directions.
Directly in front (of a microphone or loudspeaker, for example).
Circuit which is not electrically continuous and through which current cannot therefore flow.
The output voltage of a microphone when it is not connected to a load, or, when the load is about twenty times the impedance of the microphone itself.
On a multi-track tape recorder, tracks that have not yet been used.
The nominal level at which an audio system operates. See Standard Operating Level.
Ideal amplifier whose principal properties are infinite gain, bandwidth and input impedance.
A narrow band, usually on motion picture film, which carries a photographic record of sound.
A fully prepared first generation tape in final format (i.e. an edited session tape or mix-down of multi-track master).
Apparatus for producing sustained oscillations, usually by means of positive feedback between the output and the input of an amplifying valve or transistor.
A connection or conductor through which an electrical signal emerges from an electrical or electronic device, circuit, or system.
Retained non-master material (edited or not edited).
A measure of the response of human hearing to the strength of a sound. It is scaled in phons and is an overall single evaluation calculated for the level of sound pressure of several individual bands.
Producing a recording by mixing previously recorded material with new material. The musicians listen to the previously recorded tape over headphones, while the old and new program material are recorded onto a second tape recorder.
The distortion that occurs when an applied signal exceeds the level at which the system will produce its maximum output level.
1. A component of a complex wave which may or may not be an integral multiple of the fundamental. 2. A whole number multiple of a fundamental frequency.
In magnetic recording tape, a solution of magnetic particles suspended in a binder.