The Illusion of Space as an Element of Recording

Recordings create artificial spaces that don’t exist in the real world
Spatial properties shape a track’s sound alongside timbre
How we naturally perceive space affects how we hear recordings
Understanding spatial properties helps us analyze what makes a recording sound the way it does

Every recording creates its own version of space. Sounds can seem to come from places that are physically impossible—this is a deliberate artistic choice, not a limitation.
Spatial properties (where sounds seem to be, how far away they feel, the sense of room or environment) work together with timbre to define a track’s identity.
Ecological perception refers to how we naturally interpret spatial information using our everyday experience—things like judging distance by how reverberant a sound is. Understanding this helps explain why certain spatial effects in recordings feel convincing or disorienting.
In this lecture we’ll define the key spatial properties, explore the concept of the listener’s “point of audition,” and discuss why perceiving space in recordings is challenging but essential for analysis.

Hearing Invisible Sounds in Virtual Spaces

Perceiving space in recordings is different from perceiving space in everyday life
In real life we rely heavily on sight to understand space; recordings remove that
Acousmatic listening: hearing sounds without seeing their source
We need to train our ears to notice spatial cues in recordings

In everyday life, we understand space using multiple senses—especially vision. When listening to a recording, we lose all visual information, so we must rely entirely on what we hear to perceive where sounds are located.
This is a real shift. Normally, if you hear a voice to your left, you can turn and see the person. In a recording, you hear a voice panned left, but there’s no visible source—just a speaker. This makes spatial perception in recordings a learned skill.
Acousmatic listening means focusing on sounds without seeing what produces them. The term comes from Pythagoras, who supposedly lectured behind a curtain so students would focus on his words, not his appearance. In our context, it means learning to pay attention to spatial qualities (direction, distance, reverb) rather than defaulting to visual expectations.
To analyze spatial properties effectively, we need to sensitize ourselves to subtle cues—how much reverb suggests distance, how panning creates a sense of direction, how EQ changes can make something feel closer or farther away.

Understanding Listener Perspective

“Point of audition”: the imaginary position from which you hear a recording
Playback format (stereo, mono, surround) changes what spatial information is available
Stereo is the most common format—two channels, left and right
Each format has different strengths and limitations for spatial analysis

The “point of audition” is like a camera angle, but for your ears. It’s the conceptual position from which you experience a track’s spatial layout. When analyzing a recording, this gives you a stable reference point—you’re always “sitting” in the same spot relative to the sounds.
Stereo is what most people listen to: two independent channels (left and right) that create a sound field between and slightly beyond the speakers. Most spatial analysis in this course focuses on stereo.
Mono collapses everything to a single channel, so there’s no left-right information—but you can still perceive distance and depth through volume and reverb. Surround sound (5.1, 7.1, Atmos) adds channels behind and above the listener, creating a more immersive spatial experience.
When analyzing spatial properties, you need to account for which format you’re listening in. A track mixed for stereo will sound different in mono (some spatial information is lost) and different again in surround (spatial information may be expanded or redistributed).

Spatial Properties

Recordings create artificial spaces—sounds can come from “impossible” locations
Three main illusions: direction, distance, and size of sounds
Categories of spatial properties:
- Angular direction and width (left-right positioning)
- Distance and depth (how far away something sounds)
- Environment (the perceived room or space)
These properties interact to create the overall spatial impression

A recording can place a singer right in front of you while drums seem 20 feet away in a cathedral—a space that doesn’t physically exist. This synthetic, constructed space is one of the most powerful creative tools in music production.
Direction means where a sound seems to come from (left, right, center). Distance is how far away it feels. Size refers to whether a sound seems like a tiny point or a wide, spread-out presence. These are all illusions created by mixing techniques like panning, reverb, and EQ.
Angular direction and width describe horizontal positioning—where between left and right a sound sits, and how wide it appears. Distance and depth describe how close or far a sound feels. Environment describes the perceived acoustic space—a tight room, a concert hall, an open field.
These categories don’t operate in isolation. A sound panned hard left with lots of reverb creates a very different impression than the same sound panned center and dry. The interplay between direction, distance, and environment is what gives a recording its unique spatial character.

Spatial Properties and Levels of Perspective

Three levels of perspective:
- Individual sources: where is each sound placed?
- Composite texture: how do sources relate to each other spatially?
- Overall sound: what is the total spatial impression of the track?

At the individual level, each sound source has its own spatial identity: where it sits left-to-right (lateral placement), how far away it seems (distance), and what kind of space it appears to be in (its environment or “room”). Together these create a virtual image for each sound.
At the composite level, we look at how sources relate to each other. Are the vocals up front and the guitar behind? Are instruments spread across the stereo field or clustered together? These relationships create the track’s spatial texture.
The sound stage is the overall “picture” of where everything sits. Analyzing it means looking at how sources are grouped or isolated across the stereo field—whether the mix feels wide or narrow, dense or spacious.
Each sound source can appear to occupy its own unique acoustic environment (e.g., a drum in a tight room, a voice in a hall). These individual environments interact and overlap, creating the track’s overall sense of space and depth.

Integrating Spatial Dimensions

How individual sound sources combine into a composite spatial texture
Sound stage dimensions: width, depth, and distance from the listener
Holistic environment: the total spatial world of the track
Elevation (height) is difficult to achieve in stereo

At the composite level, we analyze how all the individual spatial elements add up. How do the positions, distances, and environments of each source combine to create the track’s overall spatial feel?
The sound stage is like a virtual “frame” defined by its width (left-to-right spread), depth (front-to-back layering), and the distance between the closest and farthest sound sources. Different tracks create very different sound stages—some feel wide and deep, others tight and intimate.
The holistic environment is the big picture: the total spatial world that the track creates. It combines every individual source’s environment and the overall sound stage into one unified (and often unrealistic) space. Think of it as the “room” the entire track seems to exist in.
Stereo only gives us left-right and near-far information—it can’t reliably create a sense of height. Surround formats like Dolby Atmos add overhead speakers to introduce vertical placement, but standard stereo recordings are limited to the horizontal plane.

STEREO LOCATION: ANGULAR DIRECTION AND IMAGE WIDTH

Lateral position: where a sound sits between left and right
Stereo creates the illusion of sound coming from places where no speaker exists
Phantom images: sounds that appear to originate between the two speakers
The sound stage width is defined by the leftmost and rightmost sounds

When we talk about a recording’s spatial properties, left-right positioning (lateral location) is usually the first thing we notice. In a stereo setup, sounds can be placed anywhere from hard left to hard right using panning.
The key trick of stereo is that sounds seem to come from locations where there is no physical speaker. If you send a signal equally to both left and right speakers, you hear it in the center—even though there’s no center speaker. This is a phantom image.
Phantom images are fundamental to stereo mixing. By adjusting the balance between the left and right channels, engineers can place a sound anywhere across the stereo field. The sound appears to exist at a specific point in space between (and sometimes slightly beyond) the speakers.
The sound stage width is determined by the positions of the leftmost and rightmost sounds in the mix. A track where everything clusters near the center has a narrow sound stage; one that uses the full left-to-right range has a wide sound stage.

Psychoacoustics of Stereo Sound Localization

Our brains use differences between our two ears to locate sounds
Three key cues: timing differences (ITD), volume differences (IAD), and spectral differences (ISD)
Higher frequencies are easier to localize than lower frequencies
Headphones vs. speakers create different spatial experiences

We perceive sound direction by comparing what each ear receives. Three types of differences help us localize sounds: Interaural Time Difference (ITD)—a sound from the left reaches the left ear slightly before the right; Interaural Amplitude Difference (IAD)—a sound from the left is louder in the left ear; and Interaural Spectral Difference (ISD)—the shape of our outer ears filters frequencies differently depending on direction.
ITD works best for low frequencies (below ~1500 Hz), while IAD is more effective for high frequencies. ISD provides additional directional cues across all frequencies, which is why the shape of your ears actually matters for spatial hearing.
Frequency content affects how precisely we can locate a sound. High-frequency sounds (like a hi-hat or a consonant in speech) are easier to pinpoint. This is why even a bass-heavy instrument can be localized if its attack contains high-frequency transients.
Whether you listen on headphones or speakers changes spatial perception significantly. Headphones place sound inside your head, while speakers create an external sound field. For consistent analysis, it’s important to use the same playback method and maintain a stable listening position (your point of audition).

Image Width

Shifting width - Phil Collins’ “In the Air Tonight” (1981)
Point sources - Paul Simon’s Graceland (1986)
- “Gumboots” - electric guitar sounds in the introduction
- “Crazy Love, Vol. II”
- “Under African Skies”
Spread image - Beatles’ “She Came in Through the Bathroom Window” (Abbey Road, 1969, 1987)

Image width refers to how wide or narrow a sound appears in the stereo field. A sound can seem like a tiny point in one spot, or it can spread across a wide area. This is different from position (where the sound is)—width is about how much space the sound occupies.
A point source is a narrow image concentrated in one location, like a single instrument panned to one spot. In Paul Simon’s Graceland, listen for the electric guitar in “Gumboots”—it sits as a tight point source. Reverb can slightly widen a point source, giving it a small sense of space around it.
A spread image takes up a wider area in the stereo field, with distinct left and right edges. In the Beatles’ “She Came in Through the Bathroom Window,” some instruments are spread across the field rather than pinpointed, creating a broader spatial presence.
Width is shaped by several factors: volume, timbre, reverb, and how a sound is mixed across the two channels. A sound doubled and panned to both sides will appear very wide; the same sound in a single channel will feel like a point. Engineers use width creatively to give certain sounds more prominence or to create contrast between elements in a mix.