Audio Terminology And Definitions Dictionary

 

Octave    A range of frequencies defined by doubling—or, less frequently, halving—a particular frequency. The so-called "ten audible octaves" cover the normal human hearing range from 20 Hz to 20 kHz in the following way. Note that we've added a description of the musical tones they encompass.

1   20 Hz to 40 Hz   Low bass
2    40 Hz to 80 Hz   Mid bass
3    80 Hz to 160 Hz Upper bass
4    160 Hz to 320 Hz  Lower midrange
5    320 Hz to 640 Hz  Midrange
6    640 Hz to 1,280 Hz (1.28 kHz)  Midrange
7   1,280 Hz to 2,560 Hz (1.28 kHz–2.56 kHz)  Upper midrange
8    2,560 Hz to 5,120 Hz (2.56 kHz–5.12 kHz)  Lower treble
9    5,120 Hz to 10,240 Hz (5.12 kHz–10.24 kHz) Mid treble
10   10,240 Hz to 20,480 Hz (10.24 kHz–20.48 kHz) Upper treble

 

Ohm  The basic unit used to measure electrical resistance. The electrical unit of resistance. The value of resistance through which a potential difference of one volt will maintain a current of one ampere.

 

Ohm's Law  Stated V=IR, I=V/R, or R=V/I where V is voltage, I is current, and R is resistance.)

 

OLED  (Organic Light Emitting Diode)   A relatively new and (as of this writing) comparatively expensive technology, OLED displays are said to be brighter, more efficient, and thinner, and they feature better refresh rates, contrast, and wider viewing angles than either LCD or Plasma.

 

On-Axis Response     A loudspeaker's frequency response when measured directly in front of the enclosure.

 

One-bit  Also known as BitStream, one-bit digital to analogue conversion is an alternative method to multi-bit D/A conversion developed to improve low  level signal resolution

 

Optical Soundtrack  A soundtrack that is printed directly on film stock in exactly the same manner as image frames. It appears as a continuously transparent strip of varying width against an opaque background. The projector reads the soundtrack with a photocell placed opposite a light as the film passes between them. Economically attractive, optical soundtracks first became popular in the early 1930s. (See also: magnetic soundtrack.)

 

Output   The audio signal exiting a component.

 

Output Impedance   The source impedance an amplifier presents to a loudspeaker. The lower the source impedance the greater difficulty a loudspeaker will have in feeding Back EMF to the driving amplifier, and the greater the level of control the amplifier will be able to exert over the loudspeaker.