The Proximity pattern is a set of auditory cues that create an unnerving sense of closeness. Very close sounds and fast approaching sounds have distinct, consistent acoustics (see five techniques below). The more abruptly you introduce the Proximity pattern into your music, and the more you intensify the aural properties that distinguish them, the more likely audiences are to experience chills.

Note: The five techniques below are not mutually exclusive and are often combined in pairs. 

The Proximity pattern can trigger our instinctual fight-or-flight response by tricking our brain’s object localization system into thinking something or someone potentially dangerous is nearby.

It’s theorized that we are highly sensitive to approaching or nearby sound sources (collectively called “looming” sounds by researchers) because we have less time to defend ourselves if they turn out to be dangerous. Think of how you can ignore a buzzing fly until it comes close to your ear and then cannot help but unconsciously swat it away, even though consciously you know the fly is harmless. Researchers have found that looming sounds are correlated with increased skin conductance and other defensive responses that are well-known markers of frisson.

A common feature across approach and proximity cues is the distinction between peri-personal vs. extra-personal space. Peri-personal space is the roughly six inches immediately surrounding our bodies. Different parts of our brain activate to prioritize and process sounds in peri-personal space more quickly than sounds in extra-personal space. Proximity and intimacy cues can result in chills when they indicate an unknown sound source is already in our peri-personal space. Approach cues can result in chills when they make it appear that a sound source in extra-personal space is about to quickly enter our peri-personal space.

Our listener data indicates that accelerating crescendos that involve a large, absolute change in sound intensity often induce frisson. This method is effective because loudness is a reliable indicator of distance. Even if decibel level is held constant, closer sounds are louder than distant sounds because the sound waves have less distance to cover and the same amount of acoustic energy is spread over a smaller area.  Because they can indicate a rapidly approaching – and therefore potentially dangerous – sound source, non-linear crescendos are especially effective for frisson.

In chills-inducing passages, some of the most reliable ways we see composers and performers using this technique include:

• Fast, accelerating crescendos (<1 sec) on one or multiple unison timbres 
• Slower swells (2-3 sec) where timbre entrances are staggered to enhance the build-up

These crescendos aren’t a “hack” that automatically gives listeners chills. Our data suggests that when using this technique, it helps to:

• Placement: Precede crescendos with quieter, lower-pitched sections – often including a silent pause right before the swell itself – to accentuate the change in acoustic energy
• Context: Place crescendos at the end of cadences or during exposed transitions between sections to make the swell as conspicuous as possible for listeners
• Follow-Up: Re-start the baseline or a new supporting line immediately after the crescendo to re-assure listeners and create space or a positive appraisal response

Our listener data indicates that accelerating sweeps that increase acoustic energy at higher frequencies often induce frisson. This method is effective because brightness is a reliable indicator of distance. As sound travels through the air, it loses more energy in higher frequency regions of the spectrum than in lower frequency regions. Distant sounds are therefore less “bright” than close sounds. Because they can indicate a rapidly approaching sound source, non-linear increases in brightness are therefore especially effective for frisson. 

In chills-inducing passages, some of the most reliable ways we see composers and performers using this technique include:

• Continuous, rapidly rising fundamental frequencies such as pitch glides up the register
• Staggered sounds of increasing “brightness” that create the sensation of an object moving toward you
• “Noisy” timbres with concentrated upper harmonics, especially synths with heavy reverb, high-register vocals and strings, cymbals, and gongs

These sounds aren’t “hacks” that automatically give listeners chills. Our data suggests that when using this technique, it helps to:

• Placement: Pair these sweeps with slower tempos and reduced melodic and harmonic movement to focus listeners on the changing brightness and prevent non-acoustic distractions
• Context: Use reverb, echo, and rapid rhythmic movement to make sweeps especially “noisy’ and as conspicuous as possible for listeners
• Follow-Up: Hold the high note of the sweep and leave a rest after it to create space for a positive listener appraisal response

Our listener data indicates that whispering or “breathy” or “airy” singing often induces frisson. The key to this method is that, in non-musical contexts, these vocalizations are only audible if we are close to them. When we whisper, for example, we restrict our vocal chords so that the sound does not project. With the help of microphones and headphones, however, intimate singing techniques can create the illusion that a vocalist is in our peri-personal space. This makes whispering and breathiness especially effective for frisson.

In chills-inducing passages, some of the most reliable ways we see composers and performers using this technique include:

• Close mic’d vocals in extremely quiet recording spaces that enhance the sensation of intimacy
  
• Sudden whispering, breathiness, or inhalation/exhalation, often introduced at the start of a new section or tail end of a long note to make it less expected
• Certain reed instruments that can produce an “airy” sound, especially the saxophone and bassoon (many including opera composer Puccini considered the saxophone closest instrument to the human voice)

Whispering isn’t a “hack” that automatically gives listeners chills. Our data suggests that when using this technique, it helps to:

• Placement: Use intimate singing techniques at unexpected moments (e.g. opening of a piece, upbeat before a new section, end of a long note) to make them as surprising as possible
• Context: Pair intimate singing techniques with sparse arrangements, slow tempos, and simple texture to focus listeners on the lead vocals and prevent any non-melodic distractions
• Follow-Up: Repeat and sustain intimate singing techniques to re-assure listeners they are intentional and create space for a positive listener appraisal response

Anecdote: This is a consistent trend in our listener data and is becoming increasingly frequently in pop music (some have labelled this trend “whisper-pop”).

Our listener data indicates that sounds with varying timing and intensity across a listener’s two ears often induce frisson. The key to this method is that inter-aural differences are reliable indicators of a sound source’s location. A single sound source tends to come from one location and move continuously. Rapid inter-ear variation can therefore create the illusion of multiple sound sources very close to us, or one sound source moving rapidly around us. Both interpretations are potentially threatening and can trigger a defensive response, making inter-aural differences especially effective for frisson.

In chills-inducing passages, some of the most reliable ways we see composers and performers using this technique include:

• Rapid alternating panning, where the music (or one of the tracks) is concentrated into the left or right earbud or speaker
• Using multiple mics, for example binaural recordings that create a 3D sensation
• Spatial production effects where stereo tracks are edited with varying reverb and mixing to enhance the perception of closeness

Panning isn’t a “hack” that automatically gives listeners chills. Our data suggests that when using this technique, it helps to:

• Placement: Use leaps at the very opening of songs or during other exposed sections to make them as conspicuous as possible for listeners
• Context: Feature high-frequency sounds (given that low-frequency sounds are not significantly attenuated by the head) and non-linear movement between earbuds to make inter-ear variations as jarring as possible
• Follow-Up: Prolong and repeat the inter-ear variations to re-assure listeners the spatial movement is intentional and create space for a positive listener appraisal response 

Our listener data indicates that sounds exhibiting what researchers refer to as “crackling noise” often induce frisson. These sounds result from an object being transformed by an external force, for example wood crackling when set on fire, paper rustling when crumpled into a ball, or water swishing around when a bottle is rotated.  A second element of these sounds is that they are quiet, meaning we have to be relatively close to hear them. It’s likely this method is effective for frisson because it creates the illusion of an unpredictable, and therefore potentially dangerous, sound source in our peri-personal space.

In chills-inducing passages, some of the most reliable way we see composers and performers using this technique include:

• Crunching noises when objects are deformed in irregular ways, like crumpling paper or rustling leaves
• Wet noises that mimic the sound of liquids dripping, swishing, or moving in irregular ways
• Clicking or fluttering noises that mimic the sound of objects colliding in irregular ways, like staggered finger tapping on hard surfaces, scissors opening and closing rapidly, or certain spoken sounds (sk, ch, ts, tk)

Don’t interpret this to mean that any wet or clicking sound effect will automatically give listeners chills. Our data suggests that when using this technique, it helps to:

• Placement: Use crackling noise during sections with no lead melody, or a simple repeated phrase, to focus listeners on the acoustics rather than any harmonic movement
• Context: Pair crackling noise with quiet sections and reduced textures so that even subtle swells in dynamics and jerks in rhythm are as conspicuous as possible for listeners
• Follow-Up: Prolong or repeat crackling noise effects to re-assure listeners and create space for a positive listener appraisal response