Designing Sound

This essay by Douglas Murray is a guest article on the site Designing Sound, a multi-author blog for sound design professionals. Much of the site's content will probably not be very accessible or even of much interest to others.

Murray's piece is the exception. The article is on background sound (ambient or environmental sound) and is especially rich with information. It is also very accessible, and could easily be read even in conjunction with Hearing the Movies, chapter 1.

For example, where we say

If the foreground shows us where to direct attention, the background provides a sense of presence, of a continuous, uniform space that joins the sound and image edits into the appearance of a unified physical place, a “world.”  (HtM, 11)

Murray writes that

Movies essentially need to have background sound at all times. By adding background sounds to a scene we define what the scene is, where we are, and what’s happening around us, even off screen. 

and

Whether consciously listened to, or subconsciously heard, background sounds define the space, the time and the mood of the scene. 

Where we write

A background sound common to a series of shots helps convince us that each piece of dialogue comes from the same space—although, in fact, dialogue is typically edited along with the images and is often rerecorded after the fact.

Murray says

BG sounds even define the duration of the scene. We connect shots together in our mind if they have continuous sounds running behind them. For example, if we see a sequence of shots accompanied by a steady background sound, we will gather the shots together in our minds as being from the same time and place.

And, when Murray describes the function of background in this way,

Even though we hear [ambient] sounds, and can often describe what we heard if asked, we aren’t focusing on the background sounds in a scene because we are engaged in the characters and story.

That sounds pretty much the same as our description:

The foreground/background structure ensures that narratively important figures are placed in the foreground [—] image and sound tracks are arranged in such a way that we know what to pay attention to, what is important in order for us to understand the narrative. 

Here are some other observations from the article (quotes are slightly edited).

• When the background sound changes with each shot, then we experience each shot as in its own place and time. 
• [Expected environmental] sounds are not likely to attract a lot of conscious attention, but there would be a sense of absence if they or some other plausible sounds were lacking, especially at the beginning of the scene while we are orienting ourselves to the new situation. 
• A marvelous side benefit of putting in these expected sounds is that the sound designer can think “musically” and use this palette of sounds the way a composer uses the available instruments in an ensemble.
• Absence of sound can create a tension like holding one’s breath. 
• Two tasks for the sound designer: Establish the location, then direct the audience’s point of view by withholding most sounds and selectively presenting just the desired sounds. 
• Dynamics may be a sound designer's enemy in backgrounds. Our ears prick up when we hear sudden changes in sound level and we attend to the new sound, assessing the threat or import of this sudden change. So a loud sound like a car by or dog bark or door slam can take you right out of the movie.
• Remember that the mixer will probably play your beautifully designed atmosphere track at an ephemeral or subliminal level, so that just a whiff of it bleeds into audibility. . . . This practice is so widespread that mixing a background track to a more than subliminal level becomes some sort of statement. Low level backgrounds are a convention today — perhaps to a fault.

Offscreen vs. Ambient Sound

When we hear a bark but do not see the dog or hear birdsong but do not see the bird, it can be difficult to decide whether to classify such sound as offscreen or ambience. This ambiguity points to a fundamental difference in narrative function, which in turn determines whether we expect the source of the sound to be shown. If the function of the sound is primarily atmospheric, if it serves primarily to establish mood and setting, then there is no reason to show the source. Indeed, showing the source might actually endow it with undue narrative significance. Think here of the atmospheric sound of a howling wolf against the image of a full moon; now think of that same sound, only this time the fog parts on a hilltop revealing an image of a wolf beneath the full moon. The presence of the wolf with synchronized sound asks for a much more direct interpretation. It asks us to make some narrative sense of the bodily presence of that wolf as opposed to the atmospheric presence of the call.

This suggests that one way of thinking about the difference between offscreen sound and ambient sound is in terms of an expectation determined by the needs of the narrative: with offscreen sound we expect the source to be shown whereas with ambient sound we do not expect the source of the sound to be shown. Sometimes, as with crickets at night or the wind howling, we understand that this sound could never be localized to a single sound source; such sound in that sense will always be ambient because, in a sense, it cannot be narrativized, cannot be turned into a character. (Crickets could, perhaps, (like locusts) manifest themselves as a swarm and the wind could become, say, a tornado—as it does in Twister. These are limit cases that show how ambience is bound to a general, rather than particular, representation of the environment or setting.) Even with bird song or a dog bark, where the sound could be much more easily synchronized and so be made particular, we do not expect the source to be revealed to the extent that we understand it as ambience.