1This lecture will be about the science of acoustics, the study of sound,
2in relation to urban environments such as cities.
3As an acoustic engineer myself,
4I think this is an area where we're likely to see great changes.
5In the past, researching urban soundscapes was simple.
6We measured levels of sound in decibels,
7so I used to take my sound meter and I measured the noise somewhere,
8and then I might ask a sample of people to say at what level the sound became annoying.
9With data like this, acoustic engineers have been able to build up what we call noise maps,
10maps of the sound environment.
11But actually these aren't a lot of use.
12What they do show is that the highest noise levels are generally on roads.
13Well, that's not really very surprising.
14But there's quite a lot going on that these maps don't show,
15because they can't capture the complex way that sound varies over time.
16So they ignore important issues such as the noise someone might hear from the open windows
17or gardens of their neighbours,
18and this sort of noise can be quite significant in summer.
19We don't have any databases on this sort of information.
20As well as that, these records of sound levels take no account of the fact that people vary in their perceptions of noise -
21so someone like me with years of working in acoustics might be very different from you in that regard.
22But anyway, even though these noise maps are fairly crude,
23they've been useful in providing information
24and raising awareness that noise matters,
25we need to deal with it and so it's a political matter.
26And that's important -
27we need rules and regulations because noise can cause all sorts of problems.
28Those of you who are city-dwellers know that things go on 24 hours a day,
29so city-dwellers often suffer from interrupted sleep.
30It's also known that noise can lead to a rise in levels of stress,
31due to physical changes in the body affecting the composition of the blood.
32And there are other problems as well,
33for instance if schoolchildren don't have a quiet place to study, their work will suffer.
34Now, one problem with decibel measurement is that it doesn't differentiate between different types of noise.
35Some types of sounds that most people would probably think of as nice and relaxing
36might well score quite highly in decibel levels -
37think of the sound made by a fountain in a town square, for example.
38That's not necessarily something that we'd want to control or reduce.
39So maybe researchers should consider these sorts of sounds in urban design.
40This is going to be tricky
41because just measuring decibel levels isn't going to help us here.
42Instead, many researchers are using social science techniques,
43studying people's emotional response to sound by using questionnaires and so on.
44So what exactly do people want to hear in an urban environment?
45Some recent interdisciplinary research has come out with results that at first sight seem contradictory -
46a city needs to have a sense of activity, so it needs to be lively,
47with sounds like the clack of high heels on a pavement or the hiss of a coffee machine,
48but these mustn't be too intrusive,
49because at the same time we need to be able to relax.
50One of the major problems in achieving this will be getting architects and town planners to use the research.
51Apart from studying the basics of acoustics,
52these people receive very little training in this area.
53But in fact they should be regarding sound as an opportunity to add to the experience of urban living,
54whereas at present, they tend to see it as something to be avoided or reduced as far as possible,
55or something that's just a job for engineers like the street drainage system.
56What's needed is for noise in cities to be regarded as an aesthetic quality,
57as something that has the qualities of an art form.
58If we acknowledge this, then we urgently need to know what governs it and how designers can work with it.
59We need to develop a complex understanding of many factors.
60What is the relationship between sound and culture?
61What can we learn from disciplines such as psychology about the way that sound interacts with human development and social relationships,
62and the way that sound affects our thoughts and feelings?
63Can we learn anything from physics about the nature of sound itself?
64Today's powerful technologies can also help us.
65To show us their ideas and help us to imagine the effect their buildings will have,
66architects and town planners already use virtual reality -
67but these programs are silent.
68In the future such programs could use realistic sounds,
69meaning that soundscapes could be explored before being built.
70So hopefully, using the best technology we can lay our hands on,
71the city of the future will be a pleasure to the ears as well as the eyes.