For the audiophile, “ambience” is a highly desirable acoustic quality of the listening room where sound seems to hang in the air, to have a low level but sustained presence. It is developed by coordinating the acoustic compliment in the room with the dispersion pattern of the loudspeaker in such a way that the acoustic signature of the small room is replaced by a new acoustic signature, one which defines a larger, less distinct and more spacious listening room.
The entire treble frequency range is utilized to convert the small room acoustics into a spacious listening environment. “Ambience” is too easily muted by simple sound panels and acoustical foam. Special high-end acoustics, TubeTraps are designed to attenuate the undesirable buildup of excessive bass while simultaneously redistributing the treble range in patterns that create spacious sounding listening rooms.
In filmmaking, ambience (also known as atmosphere, atmos, or background) consists of the sounds of a given location or space. It is the opposite of “silence”. Ambience is similar to presence but is distinguished by the existence of explicit background noise in ambience recordings, as opposed to the perceived “silence” of presence recordings.
Every location has distinct and subtle sounds created by its environment. These sound sources can include wildlife, wind, music, rain, running water, thunder, rustling leaves, distant traffic, aircraft and machinery noise, the sound of distant human movement and speech, creaks from thermal contraction, air conditioning and plumbing noises, fan and motor noises, and harmonics of mains power.
Reverberation will further distort these already faint sounds, often beyond recognition, by introducing complex patterns of peaks and nulls in their frequency spectrum, and blurring their temporal characteristics. Finally, sound absorption can cause high frequencies to be rolled off, dulling the sound further.
Ambience is normally recorded in stereo by the sound department during the production stage of filmmaking. It is used to provide a movie location with sonic space and normally occupies a separate track in the sound edit.