Have you ever heard the sound of voices echoing in an empty room or learned about how bats can “see” with sound? Do you recognize the cacophony of busy streets or the absence of clamour in the silence offered by in-ear headphones?
Sonic Magic: The Wonder and Science of Sound, written and directed by Jerry Thompson, explores just how powerful sound is: how it translates into visual images, creates unique acoustic experiences and can develop into technologies to help shape our quality of life.
Thompson starts by showing us the sound made visible through sand on vibrating metal plates. A B-flat played by a violin bow will create a star or cross effect while a different note pulls the sand apart in another pattern. Besides affecting sight, sound also has the ability to alter our sense of taste: experiments show how food eaten during an airplane flight may taste more bland compared with food eaten elsewhere. The loud noise of the airplane distracts our brains and hinders our ability to process taste as effectively. Louder environments are also linked with stress, anxiety, increased heart rate, fatigue, loss of sleep and social conflict.
More sound isn’t all bad. Thompson also looks at how engineers optimize audio experiences in performance halls, “mak[ing] the space sound like it’s supposed to sound.” We are taken to Boston, home of the Symphony Hall — acoustically, one of the top concert halls in the world. Here, sound engineers adjust the venue to cater to different performances, worrying about everything from floor materials to ceiling covers, ensuring the audience hears the best sound possible produced by voices and orchestras. Thompson highlights that we take the music we hear on stage for granted, without considering that it takes a lot of thought and calculation behind the scenes to produce what we hear in concert.
What spoke to me most in the documentary was the discussion of Vancouver’s “soundmarks” — the blaring Heritage Horns atop Pan Pacific Hotel at Canada Place, for example, or the distinctive bells of the Holy Rosary Cathedral on Burrard. These unique sounds build the city’s audio profile. Everyday at noon, without fail, the 10 cast aluminum horns at the harbour front bellow out the first four notes of the Canadian national anthem at 115 decibels, signalling to tourists, residents and workers that it is lunchtime in Vancouver. But as Thompson reveals, our city’s soundscape has evolved: the increased density of the city has drowned out the once-loud bells of the Holy Rosary Cathedral, capping its radius at a few mere blocks. What once was a familiar sound around Burrard Street has now become a rarity to downtown residents.
I have never thought of the city as a collection of sounds or paid much attention to its audio soundscape. But when I travel, I do miss the sound of Vancouver, which begs the question: We keep historical landmarks — we build around them rather than tear them down — but aren’t historical soundmarks just as deserving as physical structures in preserving the essence of our city?
Sound is also used in more practical applications. We meet Daniel Kish, who, having lost his sight at a young age, adapted by making clicking sounds to echo-locate his surroundings much like bats do with sonar. His amazing ability to overcome the obstacle of lost sight, shows how sound can be a gift. In advancing medical techniques, MRI-guided focused ultrasound is being used to burn away tumours and take away the pain caused by many cancers. Experiments in mice with Alzheimer’s disease has lead to applications surrounding pulse ultrasound that show a restoration of memory function. These experiments are just the beginning of the endless possibilities sound brings to our lives.
Sound is all around us. It resonates, emanates and reverberates through our bodies. It is cherished, either in abundance as music or in absence as silence from disconcerting noise. Of the five senses, the ability to hear sound is the most remarkable.
Sonic Magic premieres on CBC’s The Nature of Things this Thursday, Nov. 12 at 8 p.m.