| This lecture will be about the science of acoustics, the study of sound, |
| in relation to urban environments such as cities. |
| As an acoustic engineer myself, |
| I think this is an area where we're likely to see great changes. |
| In the past, researching urban soundscapes was simple. |
| We measured levels of sound in decibels, |
| so I used to take my sound meter and I measured the noise somewhere, |
| and then I might ask a sample of people to say at what level the sound became annoying. |
| With data like this, acoustic engineers have been able to build up what we call noise maps, |
| maps of the sound environment. |
| But actually these aren't a lot of use. |
| What they do show is that the highest noise levels are generally on roads. |
| Well, that's not really very surprising. |
| But there's quite a lot going on that these maps don't show, |
| because they can't capture the complex way that sound varies over time. |
| So they ignore important issues such as the noise someone might hear from the open windows |
| or gardens of their neighbours, |
| and this sort of noise can be quite significant in summer. |
| We don't have any databases on this sort of information. |
| As well as that, these records of sound levels take no account of the fact that people vary in their perceptions of noise - |
| so someone like me with years of working in acoustics might be very different from you in that regard. |
| But anyway, even though these noise maps are fairly crude, |
| they've been useful in providing information |
| and raising awareness that noise matters, |
| we need to deal with it and so it's a political matter. |
| And that's important - |
| we need rules and regulations because noise can cause all sorts of problems. |
| Those of you who are city-dwellers know that things go on 24 hours a day, |
| so city-dwellers often suffer from interrupted sleep. |
| It's also known that noise can lead to a rise in levels of stress, |
| due to physical changes in the body affecting the composition of the blood. |
| And there are other problems as well, |
| for instance if schoolchildren don't have a quiet place to study, their work will suffer. |
| Now, one problem with decibel measurement is that it doesn't differentiate between different types of noise. |
| Some types of sounds that most people would probably think of as nice and relaxing |
| might well score quite highly in decibel levels - |
| think of the sound made by a fountain in a town square, for example. |
| That's not necessarily something that we'd want to control or reduce. |
| So maybe researchers should consider these sorts of sounds in urban design. |
| This is going to be tricky |
| because just measuring decibel levels isn't going to help us here. |
| Instead, many researchers are using social science techniques, |
| studying people's emotional response to sound by using questionnaires and so on. |
| So what exactly do people want to hear in an urban environment? |
| Some recent interdisciplinary research has come out with results that at first sight seem contradictory - |
| a city needs to have a sense of activity, so it needs to be lively, |
| with sounds like the clack of high heels on a pavement or the hiss of a coffee machine, |
| but these mustn't be too intrusive, |
| because at the same time we need to be able to relax. |
| One of the major problems in achieving this will be getting architects and town planners to use the research. |
| Apart from studying the basics of acoustics, |
| these people receive very little training in this area. |
| But in fact they should be regarding sound as an opportunity to add to the experience of urban living, |
| whereas at present, they tend to see it as something to be avoided or reduced as far as possible, |
| or something that's just a job for engineers like the street drainage system. |
| What's needed is for noise in cities to be regarded as an aesthetic quality, |
| as something that has the qualities of an art form. |
| If we acknowledge this, then we urgently need to know what governs it and how designers can work with it. |
| We need to develop a complex understanding of many factors. |
| What is the relationship between sound and culture? |
| What can we learn from disciplines such as psychology about the way that sound interacts with human development and social relationships, |
| and the way that sound affects our thoughts and feelings? |
| Can we learn anything from physics about the nature of sound itself? |
| Today's powerful technologies can also help us. |
| To show us their ideas and help us to imagine the effect their buildings will have, |
| architects and town planners already use virtual reality - |
| but these programs are silent. |
| In the future such programs could use realistic sounds, |
| meaning that soundscapes could be explored before being built. |
| So hopefully, using the best technology we can lay our hands on, |
| the city of the future will be a pleasure to the ears as well as the eyes. |