Tomorrow belongs to those who can hear it coming

Ruth Moslin recently achieved a first class degree in audio engineering from the University of the Highlands and Islands in Scotland. For her research she wrote a paper on soundscapes and how they affect our creative, mental and ecological worlds. This is a shortened version (complete with sound effects).

By Ruth Moslin

'Tomorrow belongs to those who can hear it coming’ – a phrase used by David Bowie to promote his 1977 album Heroes. Although Bowie was most likely referring to the fluctuating political and fashionable trends prevalent at the time, the phrase has since been used in discussions relating to the earth’s sonic landscape and it’s ever-changing biophonic, geophonic and anthrophonic soundscapes.

The first known audio recording of a biophonic non-human source was captured on the earliest available commercial recording device, the wax phonograph cylinder. Frankfurt born, Ludwig Koch, caught the song of a captive shama bird in 1889 and while this is an impressive achievement alone, Koch was only eight years-old at the time. Since then, birdsong has been used in extraordinary ways as both artwork and in healing practices. (Listen here https://www.bbc.co.uk/sounds/play/b00jn4m2)

Birdsong
Combining human sound and the environment in 2015, Robin Perkins released the album A guide to the birdsong of South America which contains calls from endangered birds across the continent to raise money for non-profit organisations. While birdcalls vary through species, they are known to be beneficial to mental health, but setting aside the pig-like grunt from the Atlantic puffin, why do humans find birdsong so calming?

Birdsong falls within the frequencies known as the ‘sweet spot range for human hearing’ (1,000Hz-8,000Hz). Electroencephalography (EEG) measures brain waves and is broken up in to gamma, beta, alpha, delta and theta frequency bands, which fall within our sweet spot range. Theta waves have been shown to be strongly present during internal focus activities, such as meditation and relaxation – possibly providing the insight into why birdsong is used so widely for therapeutic uses.

Above: Setting aside the ‘pig-like grunt’ of the Atlantic puffin, humans find birdsong calming

These days recorded birdsong is not just found in relaxing Spotify playlists or BBC’s Springwatch. Alder Hey Children’s Hospital in Liverpool has played birdsong in its corridors since 2010, the recordings, which were captured at a nearby park, are seen to uplift spirits and boost relaxation. A similar concept can be found in Amsterdam’s Schiphol Airport where birdsong recordings are used in lounges to promote relaxation before flights. (Listen to birdsong therapy here https://www.birdnote.org/podcasts/birdnote-daily/birdsong-therapy)

However, unlike Ludwig Koch’s shama recording, the most mesmerising bird song will not be recorded from those in captivity – so what is the best way to capture these sounds? Paying homage to the Heinrich Hertz 1888 parabolic antenna, the parabolic shield has it’s uses for birdcall recording, its concave design, which gathers sound into a focal point can be paired with an omni-directional microphone that provides the ability to capture the very best of dawn choruses. In his book, The Singing Life of Birds , ornithologist Donald Kroodsma compares the parabolic shield and shotgun microphone for their qualities in bird call recording. Kroodsma suggests that the parabolic microphone is far more capable of capturing soft and distant sounds, however, it doesn’t capture the birds as heard by the human ear, such as that of a quasi-binaural microphone set up. Although the parabolic microphone covers a much larger area than that of a shotgun, the shotgun manages to capture more echo and uncertain sounds – making birdsong sound a little ‘smudgy’. Despite the disadvantages they pose on recording birdsong, shotgun mic’s are better at capturing low frequency sounds and are used for recording outdoor sounds such as psithurism (the sound of wind blowing through trees), which brings us neatly to the next sonic attribute – geophony.

Geophony
Geophonic sounds describe any sound created by nature, reminding us how powerful the earth can be and how it is continuously on the move. In 2020, the sounds of the melting Kongsvegan glacier in Norwegian archipelago, Svalbard, were recorded by researcher, Ugo Nanni¹, using a seismometer, where the frequencies recorded fell between 1-100hz. These infrasonic recordings were processed to be audible and contained the constant sound of cracking ice around the melting glacier, despite its visual stillness.

According a 2021 study by Noise & Health², low frequency sounds can be dangerous to humans. The study concluded that within one hour of exposure to infrasonic sounds of more than 100 dB, there is interference with the human cardiac muscle, increased nausea and sleep disorders in participants. London’s Gatwick airport is home to the largest soundscape installation that incorporates geophonic sounds – A Living River. Using over 60,000 meters of speaker cable, the installation contains a series of hydrophone recordings captured along China’s Yangtze river that plays to those walking along Skybridge, the 180m-long airport corridor, the installation is supported by WWF who also promote alternative methods of travel over aeroplanes to cut aviation pollution and aircraft noise. Listen here: https://www.dandad.org/awards/professional/2016/branding/25407/living-river/

Above: Songs of the Humpback Whale (1970) by Roger Payne showed that whales could sing and communicate in rhythm

Under water
In 1490, Leonardo Di Vinci was credited for the first noted evidence that sound travels under water. One of the most influential uses of a piezoelectric hydrophone dates back as far as World War I when Canadian inventor, Reginald Fessenden, used a hydrophone in 1914 to detect an iceberg in the hope of avoiding a repeat of the Titanic disaster two years prior. Further developments using hydrophones include arrays where several are placed across the ocean floor to record data. This method has uses for recording the position of marine life and has been modernised by the US navy who tow a hydrophone line array behind ships to locate enemy submarine positions.

Forming a creative use, the muti-platinum album, Songs of the Humpback Whale (1970) by Roger Payne showed that whales could sing and communicate in rhythm. Payne’s album is the most successful nature recording of all time and kick-started the Save the Whales movement, which eventually led to the banning of commercial whale hunting in 1986. More recently in 2023, James Crutchfield developed a hydroambiphone – a 3D underwater audio recorder which he used to record humpback whales in Alaska.

Continuous research into anthropocene soundscapes on marine life has been studied due to the qualities of hydrophones recording. The EU set limits on underwater noise pollution, so since March 2024, no more than 20% of a marine area can be exposed to continuous underwater noise during a given year and no more than 20% of a marine habitat can be exposed to impulsive noise over one day – an incredible step forward given the EU’s continuous and expanding shipping traffic.

Archeoacoustics
The combination of archaeology and acoustics (archaeoacoustics) uncovered large granite rocks known as gong rocks in the Serengeti National Park in Tanzania, believed to date back as far as the middle-ages. Similarly, ‘The Ringing Stone’ in Tiree, Scotland is thought to have arrived from the Isle of Rùm during the last ice age. These carved and decorated rocks are lithophones and when hit with a stone produce sounds believed to have been a form of communication for gathering people, warning signals and rituals. Listen to the gong rocks here https://tinyurl.com/gongrock

Sound anthropologist, Iégor Reznikoff, studied sound within painted caves and rocks and found that areas with a higher resonation rate generally contained more paintings dating back to the palaeolithic period, providing evidence that they were used as very early amphitheatres. Today, a more contemporary use of these resonating caves is found inside the Luray Caverns in Virginia, USA. An organ is fixed in place to vibrate the caves’ stalactites and is now known as the largest musical instrument in the world. Listen here: https://www.sonicwonders.org/great-stalacpipe-organ-usa/

Urban landscapes
The best example of an anthrophonic soundscape is, of course, a city. In 1928, The Daily Mail recorded the urban soundscapes of London with the specific aim to highlight traffic noise. Five of those recordings were published on gramophone, played on BBC radio and almost instantly, officials in London took immediate action to minimise traffic noise by placing limitations on the use of car horns. Fast forward to 2020, these recordings were made available to visitors at the Museum of London³ alongside updated recordings from the same locations to allow listeners compare (recognising that because of the pandemic the streets of London were significantly quieter at that time).

Lead by R Murray Schafer, the World Soundscape Project aimed to bring together research on the scientific, sociological and aesthetic aspects of the acoustic environment. The Vancouver Soundscape was one of the group’s first releases in 1973 where listeners could be re-cast to late 1970’s Vancouver with the recordings capturing the reality of a working industrial city. Two of the group’s members, Barry Truax and Hildegard Westerkamp were involved in the 1996 re-issue of the project aiming to highlight the changes in Vancouver’s soundscape over the years and provided an audible difference from the stereo Nagra analogue recorder used by the group for the first recordings.

Infrasonic sounds
Of course, another way to identify sound is to visually inspect the frequencies in audio signals from spectrogram software. By using spectrograms, bioacousticians have been able to research a range of mammals’ infrasonic sounds, particularly those of elephants. Researchers at Cornell University’s Elephant Listening Project estimate that because of elephants’ infrasonic range humans can only hear around 40% of the animals’ sounds. But by using acoustic arrays to record elephant calling, researchers have discovered that elephants have a four-octave frequency range, reaching between 27Hz and 470Hz – pretty handy when you are trying to reach your friend over six miles away. Creatively, spectrograms are also used as an artform. In late 90s a trend of artists ‘hiding’ spectrogram artwork in their music began, one of these was Cornish artist, Aphex Twin, whose track Equation was hiding his own face at the end of the track using a spectrum of frequencies, of course it could be argued that animal calls are a lot more pleasing to listen to! Listen here: https://www.youtube.com/watch?v=M9xMuPWAZW8

Biophilia
There is now evidence that humans find that biophonic and geophonic sounds more relaxing than anthropogenic sound. Naturalist Dr Edward Wilson, used the term ‘biophilia’ to describe the tendency that humanity as a whole has to be drawn towards nature. Supporting his theory is the trend of shinrin-yoku (forest bathing) – a Japanese practice of surrounding oneself in nature. To test this, researchers for BBC series, Forest 404, immersed participants in sounds of rainforests, woodlands and coastal areas to record the psychological impact it had on them. Results recorded from the study in those who practiced it included lowered blood pressure, lower heart rate and a decrease in the stress hormone, cortisol – assisting the stress recovery and the attention restoration theories. In 2017, the University of Sussex exposed 17 participants to a series of natural and artificial sounds. During listening, functional magnetic resonance imaging (fMRI) scans were produced, allowing the researchers to have a visualised demonstration on the effects of natural sounds. The results showed improved internal focus, lowered blood pressure, decrease in the body’s sympathetic response (flight or flight mode) and an increase in the body’s parasympathetic response (relaxation).

Given that every soundscape has its own unique elements which create its sonic characteristics, it would be challenging to provide only one explanation as to why they provide us with the affects they do. Without a doubt one aspect is for certain – as urbanisation grows rapidly and our natural surroundings change, this could well be an opportune time to capture our sonic landscape and map the continuous changes in our rapidly changing world.

References
1. https://edm.com/lifestyle/ambient-glacier-sounds-climate-change-effects
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8411947/#:~:text=Exposure%20to%20high%20levels%20of,as%20one%20hour%20after%20exposure
3. https://www.londonmuseum.org.uk/blog/recording-londons-soundscapes-past-present/