A Multicoloured Symphony of Sound Noises

A Multicoloured Symphony of Sound Noises

Sound noises, often referred to as ambient or background sounds, hold a unique place in the realm of auditory perception. These auditory textures, akin to the colours in a painting, encompass a wide spectrum of frequencies and amplitudes.

In the world of sound, beyond the symphonies and melodies, lies a sonic landscape that often escapes conscious attention—the realm of sound noises. These are ambient sounds that surround us, intricately woven into the auditory tapestry of our lives. Sound noises emerge from a myriad of sources, both natural and artificial. Think of the humming of your fridge, the sound of the rain or sea, the fan of your computer, distant voices and car traffic. It is a canvas splashed with colours, sound noises bring forth a palette of sonic hues, each evoking emotions and states of mind. They all contribute to the tapestry of sound noises and our auditory environment.

Good to note is that this article is about certain frequency ranges across the audible spectrum, not about we as human might consider as noise or the volume of sounds.

The Colours of Sound Noises

Much like colours in a painting, sound noises are diverse in their characteristics. The low rumble of a waterfall might elicit a sense of tranquility, while the rhythmic clatter of a train can evoke a contemplative mood. These auditory hues have been metaphorically associated with colours, such as the “blue noise” resembling the sound of ocean waves, or the “pink noise” akin to rainfall. These sonic shades offer a spectrum of emotional and cognitive experiences.

There are many coloured noises but the ones below are the most distinct:

1. Grey Noise:

Grey noise is characterized by equal energy per octave, rendering it perceptually flat across the entire audible frequency spectrum. It lacks the prominence of higher frequencies found in white noise.

Frequency Range: Throughout the entire audible range.

Use: Grey noise is often used for psychoacoustic studies, as it allows researchers to explore how humans perceive sound energy at different frequencies.

2. White Noise:

White noise exhibits equal energy across all frequencies, creating a consistent sonic spectrum akin to the static on a television or radio.

Frequency Range: Throughout the entire audible range.

Use: White noise is commonly used for sound masking, promoting concentration, and aiding sleep.

3. Blue Noise:

Description: Blue noise has a higher energy in higher frequencies, rendering it a sharper and more pronounced sound than white noise. It is akin to the sound of ocean waves crashing.

Frequency Range: Increases logarithmically with frequency.

Use: Blue noise finds application in audio testing, especially for assessing high-frequency capabilities of audio equipment.

4. Brown Noise:

Brown noise, also known as red noise, has more energy in lower frequencies (twice as strong as Pink noise), creating a deeper, rumbling sound reminiscent of a thunderstorm or a waterfall.

Frequency Range: Decreases logarithmically with frequency.

Use: Brown noise is favoured for relaxation, stress reduction, and aiding sleep. Recently a lot of articles have popped up of the use of brown noise to help focusing when you have ADHD.

5. Pink Noise:

Pink noise has equal energy per octave, resulting in a balanced frequency spectrum that decreases as frequency increases. It has a smoother and more natural sound compared to white noise.

Frequency Range: Throughout the entire audible range.

Use: Pink noise is beneficial for enhancing focus, improving cognitive performance, and aiding relaxation.

6. Violet Noise:

Violet noise, also known as purple noise, emphasises the highest frequencies, making it a sharper and crisper sound compared to white noise. It resembles the hiss of a high-powered waterfall.

Frequency Range: Increases logarithmically with frequency, with higher energy in higher frequencies.

Use: Violet noise has potential applications in improving hearing sensitivity and aiding auditory processing.

Deeper into coloured noise

In the book Sonic wonderland, A Scientist Odissea of Sound by Trevor Cox he mentioned that he moved his head from side to side, voices in the room change as if someone was rapidly altering the settings on a hi-fi’s graphi equaliser.  This colouration was caused by a change in the balance of the sound, with some frequencies being boosted while others were suppressed. In short he was experiences noises this is what he had to say about the colouration of noises:”

It might seem odd to talk about the colour of a sound …The link between colour an sound goes back many centuries, with Sir Isaac Newton spotting the similarity between the distance his prism spread out light colours and the lengths of strings needed to sound out a musical scale”

Trevor Cox mentions that also today, acoustic engineers use terms as ’white and ‘pink’ noise. In a way it is similar as he explains when paints are mixed together the frequency balance of the reflected light changes from the original colours presenting a different colour. He explains further that blue paint reflects light of a higher frequency than red paint and therefor acoustic engineers use colours to describe the dominant frequencies in sounds,

What is interesting is that he also found that sound most likely influenced the way our ancestors painted. He mentions acoustic archaeologist Steven Waller who wrote a paper on this subject. (We delve into this subject in another blog) apparently the sheer volume of evidence that prehistoric rock art was influenced by cave acoustics is growing. But Cox does refer to David Lubman, a retired aerospace engineer who has been applying acoustic science to archaeological sites, warns that correlation does not necessarily mean causation.

Benefits and Negatives

The benefits of sound noises are multifaceted. They can mask intrusive sounds, enhancing concentration and aiding relaxation. Studies (see below this article) highlight the positive effects of sound noises on cognitive performance and stress reduction. However, excessive exposure to certain sound noises can lead to noise pollution and even adverse health effects. Our world is increasingly becoming louder and louder. Interestingly enough these coloured noises can be used to mask the “noise” from the world around us helping us to relax or focus. Also there are more and more experiments and research is done to find the benefit of these noises for healing in hospitals, to enrich musical soundscapes and increase productivity in normal noisy environments.

Brain processing

The human auditory system’s response to sound noises is an interplay of neural processes. When exposed willingly to sound noises, the brain’s default mode network can deactivate, promoting mindfulness and concentration. Neuroimaging studies, such as those by L. Liikkanen (see the last one of the list, below this article), illuminate the brain areas involved in processing sound noises, shedding light on their cognitive and emotional effects. The world of color noise offers a diverse spectrum of auditory experiences, each with its unique frequency distribution, emotional impact, and cognitive effects.

Self Help versus the research

If you are inspired to start listening consciously to noises it is good to note, most scientific research on this subject is not a 100% clear on how often, how to use, what colour to use exactly for what kind of mental effect you want to reach. Wether it is to focus, to mask sounds or fall asleep or stay asleep, the best advice we can give you is to experiment with the different noises in different situations. You can use the description of the colours above as a starting guideline. Experiment with different factors: the colour, the volume and the exposure time and see what works best for you. Our tracks are made in such a way you can easily put them in a loop. To read further at the bottom of this articles are some interesting links.

You can purchase our album with the different noises here: @claudio

Interesting research and articles to delve into:

Spectral Content (colour) of Noise Exposure Affects Work Efficiency: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7986458/

Effects of masking sound on train passenger aboard activities and on other interior annoying noises: http://www.diva-portal.org/smash/record.jsf?pid=diva2:341431&dswid=-2379

Effects of sound source localization of masking sound on perception level of simulated tinnitus: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8795453/

Unintended Consequences of White Noise Therapy for Tinnitus-Otolaryngology’s Cobra Effect: A Review https://pubmed.ncbi.nlm.nih.gov/30178067/

Cognitive Performance and Sounds: The Effects of Lyrical Music and Pink Noise on Performance

https://inside.nku.edu/content/dam/gero/docs/NYSA/Nysav1/Chitwood_Cognitive Performance and Sounds.pdf

Different Effects of Adding White Noise on Cognitive Performance of Sub-, Normal and Super-Attentive School Children https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4231104/

The Effect of Noise Exposure on Cognitive Performance and Brain Activity Patterns: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6901841/

Background white noise and speech facilitate visual working memory: https://www.biorxiv.org/content/10.1101/2020.04.07.030114v1.full.pdf

Can pink noise help you fall asleep


Musical activities predispose to involuntary musical imagery


To read more in sound in general and also noises we can recommend: Sonic wonderland, A scientist odissea of sound by Trevor Cox

If you are interested in de description and the technical aspects of the colour noises we can recommend the wikipedia page https://en.wikipedia.org/wiki/Colors_of_noise#White_noise

Brainwaves, Binaural Beats 

Brainwaves, Binaural Beats 

Where do technology and sound meet and can actually influence our brainwaves? Binaural beats offer a realm of potential and have an ability to influence or more exactly entrain our mental states through electrical brainwave activity.

Science Behind Binaural Beats

The effect of binaural beats lies in their ability to tap into frequencies that are perceived, not heard, by the human ear. By playing two slightly different frequencies in each ear, the brain generates a third tone, unlocking aural illusions that influence brainwave activity to that frequency. For optimal effectiveness to produce these beats they require frequencies under 1000 Hz. By listening to specific binaural beats they can entrain your brain to a specific brainwave state.

Decoding Brainwaves

The interplay of neurons within our brains forms the basis of our thoughts, emotions, and behaviors. These brainwaves show that these neurons seem to converse with one another. They can be detected through sensors placed upon the scalp, (EEG) the measured oscillations are then categorized into bandwidths/brainwaves. Each brainwave range represents a different state offering a glimpse into the diverse tapestry of human consciousness. To give an example beta waves stand for alertness and are necessary for the normal busyness of life while delta waves often represent deep sleep. A bit below you can find a list with the different brainwaves and the binaural beats to possibly experiment with:

Unraveling the Historical Thread

The history of binaural beats traces back to the 19th century, gaining comprehensive recognition through Oster’s meticulous study in 1973. This auditory investigator capitalized on the brain’s response to subtly varying frequencies, producing vibrations now known as binaural beats. The difference between the two sounds must have a frequency difference of less than 30 Hz to allow our brain to perceive the third frequency consciously. Above 30hz it becomes a normal listening experience because beyond frequency differences of 30 Hz, the two tones are perceived separately. This threshold seems to vary depending on the stimulation technique that is used.

The Main Brainwaves

Delta: 1-4 Hz.
Delta is the lowest frequency state, and it’s linked to:

  • Deep sleep
  • Meditation
  • Cortisol reduction/DHEA increase

Theta: 4-8 Hz. Theta binaural beats are linked to:

  • Meditation
  • Deep relaxation
  • Creativity

Alpha: 8-14 Hz. Alpha brain waves are linked to:

  • Relax and focus
  • Reduce Stress
  • Increase learning capabilities
  • Flow

Beta: 14-30 Hz. Beta brainwaves are linked to:

  • Keeping your attention focused
  • Analytical thinking and solving problems
  • Stimulating energy and action

Gamma: 30-100 Hz. Is linked to:

  • Increased cognitive enhancement
  • Attention to detail, helping in memory recall <interesting research with Alzheimer>
  • A different way of thinking

Best for gamma up to 40HZ based on different research. And above 40 HZ the binaural beta is technically not a beat anymore.

Mental health

Our brainwave profile weaves with our daily experiences, shaping our emotional and neuro-physical health. Brainwave patterns can give us insight in a multitude of conditions, from anxiety disorders and sleep problems to depression and ADHD. Brainwaves offer insight into these facets of our mental and emotional health. To give a very simplified example if you have a lot of beta waves while you supposed to sleeping it will be difficult to sleep. This offers the door to improved well-being by experimenting with brainwave entrainment using binaural beats.

Using binaural beats

There is more and more research on using binaural beats (some is enlisted below this article). There are no documented side effects of using binaural beats but we do advice to use your common sense. Ensuring that your headphone sound levels remain safe is for instance crucial to avoid long-term hearing loss. (Yes you do need headphones to perceive the binaural beats). Consultation before using them with a medical professional is advisable for those with epilepsy, as research in this area is ongoing. Some studies hint at increased sensations of sadness or short bursts of anxiety during binaural beat listening, although the full extent of their therapeutic impact is still being researched.

Although binaural beats have been linked to enhanced emotions, and entraining brainwave states the response is subjective, making it essential to explore and find beats that resonate with one’s individual needs. So the real advice is experiment with the time, volume, the kind of beats and the individual frequency. To assist you in this as Flower of Sound, there is an album available with all of the individual pure frequencies per brainwave and an album that puts the whole frequency range within a specific brainwave in one track. Binaural Beats Full Spectrum Range can be categorised as a non-ordinary listening experience to experiment further with the power of sound.

Brainwaves and Immersive Soundscapes

This field of brainwave entrainment, also offers a new possibility where brainwaves merge harmoniously with immersive nature soundscapes. As listening to nature sounds comes with its own set of benefits. Nature Brainwaves merges these nature soundscapes by using microphones capable to record full 360 soundscapes in combination with binaural beats.

The idea behind this union is an immersive auditory listening experience that guides listeners to desired states of consciousness. As we listen to the binaural beats, the ambient immersive soundscape envelops us, mimicking the way living beings perceive acoustic spaces. This fusion offers a natural and less stressful alternative to traditional stereo signals so it can be used for medium to long listening sessions. Unlike some platforms that reduce the volume of these frequencies to minimize “annoyance,” Nature Brainwaves embraces their presence, allowing the binaural signal to be consciously and physically perceived.

Nature brainwaves and Binaural Beats Full Spectrum Range use 200 hz as a more pleasant and low but still hearable tone than higher frequencies that are less comfortable to listen.


About entrainment:
Binaural beats to entrain the brain? A systematic review of the effects of binaural beat stimulation on brain oscillatory activity, and the implications for psychological research and intervention


Scientific America (Auditory beats in the brain)


University of Birmingham


Massachusetts Institute of Technology


Modulatory Effect of Association of Brain Stimulation by Light and Binaural Beats in Specific Brain Waves


National library of Medicine

About the use of 40 hz


From Ecstasy to Trance (Part 1)

From Ecstasy to Trance (Part 1)

In recent years, I have spent a significant portion of my time delving into two axes. One involves delving into immersive technological tools and their applications on the auditory apparatus. While the second revolves around the role of sound on the emotional states of living beings and beyond.

I admit that at the beginning of my studies, my approach to the second subject was a mixture of skepticism towards a holistic world I had never approached, and in its track a lack of reliable sources. So, overcoming the initial skepticism and steering clear of the allure of sensationalistic readings, I embarked on a fascinating journey, which is founded on themes such as neuroscience, anthropological research, deep listening and sound as the main key to trigger undiscovered human potential.

The topic of how music and sound influences your state of being, initially viewed as a fringe of the sonic world, reveals its fundamental influence on all fields of science and the study of matter. As well as it touches the very existence of our being—both in conscious terms and in terms where the unconscious is the protagonist. After all, we are vibrating bodies in a universe that vibrates, and it should not surprise us that these infinite and boundless forces are omnipresent.

I am here to introduce one of the topics that has particularly struck me: the influence of sound/music on altered states of consciousness. It’s a subject still debated and far from unanimously recognised scientific validation, but this doesn’t diminish the significance it holds.

This introduction has been necessary to understand and hopefully follow, in the simplest and clearest manner, the series of articles I will write on this topic.

Part 1

Talking about ecstasy and trance in the same article can lead to confusion because the two terms are often interpreted with similar meanings both by scholars and in the collective imagination. ln reality they are two different emotional states or state of consciousness, what they have in common is the search for spiritual and emotional healing that has characterized all of humanity since the dawn of time as my favourite author Gilbert Rouget also mentions.

To write this article I am making use of the valuable studies and research done by this Gilbert Rouget (1916 – 2017) a French ethnomusicologist and researcher who in the book Music and Trance, The Relationships between Music and the Phenomena of Possession, has well explained the meaning of ‘mystical/emotional acting that leads man to the search for ecstasy and trance. Most of the claims I make can be found in his book.

Now with my limited knowledge and with the respect that this subject demands, I will try to explain in the simplest and most subjective way possible these emotional states and take you on the journey I took and resulted in my sound journey From Ecstasy to Trance.

Ecstasy and Trance

Inherent in each of us ecstasy and trance touch territories of the unconscious not yet rationally explainable. They touch complex aspects of human existence and are therefore susceptible to manipulation by phantom healers, spiritual waifs and swayed by opinions and distinctions especially when viewed from a religious or spiritual rather than a social or rational point of view.

Let me start by saying that both ecstasy and trance are temporarily emotional states otherwise we speak of psychic pathology or mental disorder. Both states require that one is voluntarily willing with mind and body to enter this non-ordinary state of consciousness.

During the experience of these states people report to feel completely different from their daily life, they experience life completely different as life itself changed. Visual and auditory hallucinations (ecstasy) and divinatory possessions (trance) can often occur.

To simplify the concept and make it clear from the beginning, let me start with the difference between the two terms:

Trance is related to sensory overstimulation, (dances, singing sociability and ensemble rituals ) while ecstasy on the contrary is mostly a deprivation of the senses (solitude, silence, fasting self hypnosis).

Below you can find the  diagram used by Rouget that effectively explains the elements that characterise these two states for the occurrence of phenomena :


  • Stillness
  • Silence
  • Solitude
  • Crisislessness
  • Sensory deprivation
  • Recollection
  • Hallucinations
  • Visions

Trance :

  • Movement
  • Noise
  • Society
  • With crisis
  • Sensory overstimulation
  • Amnesia
  • Absence of hallucinations.

Obviously, one cannot imagine that this scheme leads to the total differentiation of the two phenomena. It is much more complex and carries with it a series of overlaps that can give rise to contradictions and further confusions. So to simplify let me say that one enters one of the two states properly if all the elements from Rouget scheme occur. On the other hand one cannot speak distinctly of a state of ecstasy or trance but of a continuum between the two phenomena.

A good example is the individual/solitary experienced Dhkir state which is more described like a state of ecstasy than trance but it is embedded in a secular Sufi trance ritual (famous twirling dancers).

As already pointed out the state of ecstasy is by its very nature an inner quest, and comes from a practice that has immobility, silence solitude and sensory deprivation as its cornerstones. Therefore it is incompatible with music which is dynamism sociality sensory excitement. Certainly there are instances when at deep levels of meditation one can hear melodies, chants or specific motifs but these occurrences are caused by sound hallucinations also called “mystical sounds” that arise from the ‘unconscious and manifest as a call of the innermost memory and are therefore a signal from within our being.

Trance on the other hand needs external stimulation almost always accompanied by music. Sometimes only rhythms, other times only with melodic and incantatory chants or other times still religious litanies but still from an external audible and participated signal. It should be added that trance is a transient state of consciousness (hence the word trance) where a part of oneself is revealed in an almost uncontrolled way, while in ecstasy one is in oneself and inwardly one finds bliss without having any kind of possession phenomena.

Trance then, is a transient state where for a given period we allow a spirit, entity to be represented in our body so we become something else and/or someone else. There are different types of trance: that of communion, ritual and religious and that of identificatory possession. The latter is triggered when the adept under certain circumstances represents the deity, the spirit ( eg vodun, djiin ) that has been called during the ritual. It often requires hours of dancing, chanting dancing, accelerating and crescendo before this can occur.  For example, in both Benin and Aleppo rituals several cults/confraternities use music and thus the dance that arises from it to bring the participants at a psycho-physical level of exhaustion. By pushing and crossing the limit of tolerance of these external stimuli beyond a threshold one enters states of transcendence where supernatural behavior, sometimes of extreme violence, self-flagellation up to episodes leading to the death of the possessed can occur.

Role of Music

What is the role of music in the arising of these phenomena?

To simplify: a certain kind of music played insistently activates dance, which combined with the right preparation, intention and stun can lead to trance.

But what kind of music?

In the collective imagination it is the drum that is often represented as the instrument that causes trance, just think of shamans but this is not always the case indeed…

From the direct testimonies of scholars present at the ceremonies, a fundamental role is played by the voice: not only the beautiful singing that leads to transcendence but even more important is the often overlooked meaning of the words. The language circumscribed to the type of culture of reference, singing about the exploits of the saints, or the cherished places and instil the stories that tell the stories of the ancestors and the patron deities of the community. It is rare if not impossible to enter trance if one is a stranger to the culture of that particular cult.

In the second part I will explore the role of music in relationship to trance from the viewpoint of philosophers like Plato or Aristotle and mystics like the Persian Ghazzalî or Rumi.

Epigram at 01 minute