phōnographs

Sonorous Landscapes will use both light and sound to create an image or impression of the urban landscape that shows human and non-human activity over time. It will capture sound as phōnographs (usually referred to as sound spectrograms or spectrographs), much like light is captured by photographs. Photographs usually offer snapshot of a moment. In this case, we will be creating snapshots not of a moment but of a long duration – a little like a long exposure photograph. The video below shows an animation made from hundreds of phōnographs, each one showing 15-seconds of the soundscape.

Below is a single frame – it is full of descriptive information about the environment.

So, what do these images tell us and why is it interesting or useful? First, it may help to explain in a little more detail what a phōnograph is. A phōnograph visualises sound as it changes over time. In the image above, as your eye moves from left to right, you are looking at how sound changed over the 15 second of the capture. The low frequencies are towards the bottom of the image, the higher frequencies towards the top. The brightness shows how loud a sound was. The phōnographs above capture audible sound (from 20 Hz to 20 KHz), so they show things that we can hear, such as cars, birds, horns, and machines. Most of the sound created by humans is in the lower frequencies – that’s the bright areas towards the bottom. Much of this is what we think of as noise – incidental sounds created by things like engines in cars, lorries, and buses, as well as the sounds of tyres, machines, and all manner of banging and hammering. These kinds of sound aren’t intended to communicate anything, although they do tell us a lot about what is going on in an environment. Sounds in the middle and upper part of the image are generally more intentional and communicative – birdsong, horns, car alarms. These sounds generally have a purpose, although it might not be relevant to us individually or even as a species.

The phōnographs above were created by prototypes of hardware and software that are being developed to capture the sonourous landscapes of Slough’s Urban Forests. This particular prototype is being tested in a back garden in Hackney – as I sit here writing this, I can hear sparrows and bluetits, a passing bus, the rumble of an underground train, and the quiet roar of a gas boiler flue – evidence of the unusually cold spring weather. If I sat here for an hour or so, narrating the unfolding soundscape, I may be able to make some interesting observations about the changing rhythms and cycles of activity over that period. But what if I want to understand how the rhythms and cycles of activity change over the whole day, over the week, the month, the year? What if I want to know how these rhythms and cycles are changing over longer periods still? This is where phōnographic portraits of the landscape can help. By developing software to capture, process, and visualise the soundscape, Sonorous Landscapes will be able to bring out the rhythms and cycles of behaviour in urban environments not only minute to minute, but also day-to-day, month-to-month, and year-to-year. By visualising the sonic activity of birdsong, bat calls, and some insects in particular, these phōnographic portraits will be able capture the biodiversity of the environment and how it changes over these various timescales. By looking at periods of months and years, this approach will be able to show how tree planting and tree maturation, for example, correlate with changes in biodiversity – or indeed how urban development, increased human activity, or tree felling correlate with biodiversity.