With or without Sound // A Report on etransâ€™ three Projects on Sound for Electric Powered Vehicles
It is perhaps first via the silent cars that we have become aware of to which high extend car noise characterises our perception of cities, and how we simply accept and have learned to live with the noise Mette Mikkelsen, etrans
1st edition, 1st print run 2012 Responsible: Project Manager Mette Mikkelsen
Authors: Main author, Industrial Designer Anne-Mette Clausen, with Contribution from Director Thomas Gadegaard, ECTunes, and Sound Designer Yann Coppier, Studio Ovale Editor: Kirsten Bohl
Picture editor: Anne-Mette Clausen
Photos: Anette Flinck, Anne-Mette Clausen, Allan Schmidt, Bo Borbye Pedersen et al. Graphic Design and Layout: JE;SU/Gul Stue
Published by the etrans project, Designskolen Kolding, Ågade 10, 6000 Kolding, Denmark ISBN: 97 88 79 07 75 353
Copyright: etrans, Kolding School of Design, Denmark All rights reserved
Photographic, mechanical, digital or any other form of reproduction from this book is permitted only in accordance with the agreement between Copy-Dan and the Ministry of Education. Any other usage without the written consent of the publisher is prohibited by applicable Copyright Act. Exceptions to this are extracts for use in reviews and discussions.
With or without Sound // A Report on etransâ€™ three Projects on Sound for Electric Powered Vehicles
1. Preface // 06 etrans’ Project Manager Mette Mikkelsen, MA Design
2. Introduction // 08 A Safety-Related Problem – and a Great Advantage in Cities and for Motorists // 09
3. Background for the Sound Projects // 12 We have become accustomed to hazards making noise // 13
4. Methods used // 16 5. About the Individual Sound Projects // 18 Soundlessness – Opportunities instead of Barriers // 55
6. about Traffic Safety // 58 Silent Hybrids and Electric Cars affect Traffic Safety, by Thomas Gadegaard, Director and Founder of ECTunes ApS // 59
7. ECTunes’ Experiences // 66 ECTunes’ Experiences with the Project and Methods, by Thomas Gadegaard // 67
8. Feedback on the etrans Project // 68 Experiences with the project (sound design part) and the userdriven method from my point of view, by Yann Coppier, Studio Ovale // 69
// New Sounds will create Security without ruining the Gift of soundlessness
Cars of the future can sound like anything at all; sound and identity can more or less be separated, and new combinations can be created and lead to completely new experiences. Here, design can play a part in creating our world. This is one of the experiences from etrans’ work with sound for electric cars. Another experience is that users are conservative in their choices. They have preferred the sounds they know, or something similar, but that is, as Thomas Gadegaard from ECTunes writes in his contribution, not what is most important. “The most important thing is that we play a part in starting a debate about how we can make the electrically powered vehicles of the future more secure. Is sound the correct means to increase the security for pedestrians and in particular the blind and those with impaired vision? If so, how do we do it as best as possible without increasing the already noise polluted city environment?” he asks. It is perhaps first via the silent cars that we have become aware of how high a degree car noise characterises our perception of cities, and how we simply accept and have learned to live with the noise. My dream is cities with a minimum of sound, and we have experienced it as a paradox that we work with sounds for electric cars, when the quietness is so liberating and so far less of a strain. But, our task is to turn electric cars into a commercial success, and the very first barrier we registered, was exactly the lack of sound. A group of students from Kolding School
of Design conducted a preliminary investigation for us on users’ attitudes toward the electric car, and one of the groups interviewed, among others, an elderly lady. She enjoyed driving but she would never own an electric car. She wouldn’t dare ride in it if cyclists and pedestrians couldn’t hear her. “Grandma” as they called the lady, came to define a major task in etrans, the task of finding a solution to the paradox of creating safety without destroying the gift of soundlessness. We have achieved exciting results and via user surveys and prototypes we have come up with sounds that are solely activated at low and dangerous speeds. We hope that Industrial Designer Anne-Mette Clausen’s thorough description of the process and methods, and the thinking that has been behind all of the individual projects, can inspire in other design processes and that the contributions from Director Thomas Gadegaard and Sound Designer Yann Coppier, Studio Ovale, can be useful knowledge for others who will develop sounds. We are glad that our co-operative partner ECTunes has received important input for further development of ECTunes’ sound core and received examples of how entire sound landscapes can be constructed, and can only be pleased about this contribution to create a commercial success. Mette Mikkelsen, MA Design, Project Manager, etrans
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// A Safety-Related Problem – and a Great Advantage in Cities and for Motorists
The soundlessness in electric cars constitutes a safety related problem in cities; more are struck by them because they don’t hear them coming, and soundlessness is, therefore, a significant barrier in relation to the acceptance of electric cars. But, soundlessness is also an advantage: It reduces the noise level and makes driving electric cars a very comfortable, relaxing and unique experience. Therefore, we have not simply worked with creating sounds, but in the last two projects, we have to a great extent also paid attention to preserving the advantage that lies in the soundlessness. The three projects represent three ways of working with sound for electrically powered vehicles. They have, in part, different purposes and achieve different results. Overall, they each have the purpose of creating debate on the topic in their own way: From e sound with elements of entertainment and play, and with a high degree of user involvement in Sound ’n’ Safe II that makes it possible to set new, realistic sounds on up to now neglected electric powered vehicles to Sound ’n’ Safe III, which with its experimental sound tableaus and its innovative construction creates a stir and new experiences. It will be natural to combine the e sound and Sound ’n’ Safe projects in order to be able to investigate how the sounds are perceived
from inside the car. In relation to Sound ’n’ Safe III, it also gives the possibility to test the speeder’s impact on the sound systems to a greater extent.
Design and user-driven innovation Our fundamental method is user-driven innovation and our experience is that user-driven innovation to a high degree can contribute to the product development, but it is no guarantee or innovation ”pusher”. Therefore, we have supplemented with design driven innovation to show what it can do in relation to creating new experiences and new products that, among others, differ markedly in their expression from what we know and what we envisage. All projects involve user input to a greater or smaller degree, and one experience is that users cannot create innovation alone. There must be one who can interpret them deeper than simply on the immediate statement. Therefore, a combination of user-driven and design driven innovation is an advantage. The user-driven ensures that one comes close to expression and needs relevant to the user. The designer can ensure the new creation that is necessary to bring new and better solutions into play. Without the user driven, one risks creating products and services that are far from what users will adopt or can live with.
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People are quite good at getting used to new things, but it requires time.
The Limitations of the Project
Still many Factors to investigate
The project has been time wise relatively limited resulting in lack of time to carry out user surveys that extend over a longer period of time and provide the opportunity to investigate the userâ€™s relationship to sounds over time. Innovative or new things require adaptation. People are quite good at getting used to new things, but it requires time. Testing the same sound over a longer period of time could, perhaps, has reflected another preference. What our test shows is whether users like these sounds at a given point. The test, therefore, paints a picture of what sounds they are most willing to accept. The final sound suggestion represents a compromise and is â€?most advanced, yet acceptableâ€?, as the designer Raymond Loewy1 has expressed it. You can listen to the sounds at www.etrans.dk
There are still many unknown factors, which can be investigated in relation to sounds for electric vehicles, and that will give new input and ideas. Here, there is a great opportunity to change the perception of urban space, perhaps a whole city. What happens, for example, when many different electric car sounds are played at the same time in a city at a crossing? Should there be stringent guidelines for how the sounds should be in expression and scope? How does one avoid creating new noise pollution? How does one create safety when it comes to silent cars? Until now, these things have not been decided upon in Denmark, whereas e.g. both the USA and Japan have legislation stating that there must be a minimum of sound from vehicles so the blind and other pedestrians can hear them.
Raymond Loewy was a French-American industrial designer who lived from1893-1986. He has, amongst others, designed the Coca Cola bottle and the Lucky Strike cigarette box and is known for the streamlined design of, e.g. steam locomotives. The MAYA, Most Advanced Yet Acceptable, principle is about products being changed but that there needs to be a fine balance. They may not be too different, if people are to feel safe having them in their homes. Source: Wikipedia.
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Background for the
// We have become accustomed to hazards making noise In traffic, we orient ourselves to a great extent with the aid of hearing. We have become accustomed to hazards making noise and it will take time before most people have become accustomed to some cars being soundless. In the first research phase of a course project on the industrial design course at Kolding School of Design, it emerged that the soundless motors of electric cars create worry and uncertainty, especially among the elderly. One fears that one, as a driver of an electric car, will not be heard by soft road users, and if one is a pedestrian or cyclist, the fear is that one will not notice the quiet car. This is one of the barriers for users. Another is that some of the users miss the identity that traditional car and motorcycle sounds create. In etrans’ anthropological user studies2 several users said that an electric car without an engine sound is not perceived as being a ”real” car. The car is, to a high degree, something that the user identifies himself with and that is perceived as a representation of whom that person is and what values he has. The engine sound is a direct reflection of what the engine does, how fast it drives and how much horsepower it has. Engine sound has existed since the advent of the fuel driven car and is, therefore, very closely associated with the car’s identity and function. In some car brands, it is even a characteristic brand name that can clearly be recognised among other car brands and contributes toward creating a certain perception of the car, both in and outside of the car.
In the electric car, this part of the current vehicle’s identity is absent, and therefore driving in an electric car is perceived as being so different and partly incomprehensible. etrans’ study showed that male users, in particular, felt a lack of potency and identity and the lack of sound contributed to a great extent to creating mistrust and displeasure with the electric car. During the course of its lifespan, the etrans project has worked with electric vehicles’ sound problems four times with, respectively, Sound’n’Safe autumn 2009, e sound autumn 2009-spring 2010, Sound’n’Safe II Oct-Nov 2011 and Sound’n’Safe III in Nov-Dec 2011. The task has been to create a sound that could provide safety without destroying the advantages of the soundlessness. For it isn’t just soundlessness, but also the noise, that is dangerous: The Danish Environmental Protection Agency has calculated that between 200-500 people die annually as a result of traffic noise. There are equally as many who die in traffic accidents3. Most recently, The Danish Cancer Society has launched a research project on the correlation between traffic noise and cancer. Senior Researcher Mette Sørensen and her team have started the task now, after first having shown in 2009 that traffic noise increases the risk of having a stroke (blood clot or bleeding in the brain). According to her study, the risk for those over the age of 65 having a stroke increases by 27 percent each time the traffic noise rises by 10 decibels4.
Find the report at www.etrans.dk/ index.php?id www.mst.dk/Virksomhed_og_myndighed/Stoej/trafikstoj/stoejogsundhed/ 4 www.cancer.dk/Nyheder/nyhedsartikler/2012kv1/trafikstoejogkraeft.htm 3
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overview of the projects
Sound ‘n’ Safe I, autumn 2009
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e sound, autumn 2009 - spring 2010
e sound lite, 2010
Sound ‘n’ Safe II, Oct-Nov 2011
Sound ‘n’ Safe III, Nov-Dec 2011
Design Project The New World, April 2009, by design students LĂŚrke Thorst Balslev, Birk Marcus Hansen, Camilla van Norde, Soleil Zumbrunn and Signe MĂĽrbjerg Thomsen.
// Methods used User-driven Innovation
User-driven innovation is used as a method for involving users and their needs and to target results toward the target group. But also in order to gain input for innovation, as experts are typically not the best at looking with fresh eyes on their subject area. In addition to this, users have frequently gathered practical experiences that can contribute to new thinking and optimisation.
The projects Sound ‘n’ Safe II and III are relatively brief studies, where in a short amount of time one goes over the same as in a correspondingly longer study with development, user tests, feedback analysis, and adaptation based on the analysis.
User-driven innovation functions best in a combination with designdriven innovation, where one both pays attention to the user’s feedback and gives space for renewal via the designer’s adaptation and interpretation. Testing on users will always be essential in relation to developing an optimised, functioning product that people adopt, understand and can relate to. Among others, it gives the opportunity to gain reactions from groups such as the visually impaired, whose experiences it would otherwise be difficult for designers to study. Therefore, user testing is still necessary at several stages, but the most decisive thing is how one uses the feedback users provide. Does one do as the user says, or does one observe reactions and interpret them on the said and the unsaid and combine with new ideas for creating a new experience and a product that is not available yet? That is to say, innovations that start from the user’s acknowledged and non-acknowledged needs. Users don’t know how they will solve a problem or e.g. form a sound so they can like it and feel that they cannot live without it. But, they can say and show when something functions and hits the bull’s-eye for them and show their reactions to a certain sound. 5
It is valuable to carry out such relatively small and inexpensive courses, where one develops prototypes and gathers experiences for better or for worse. One can certainly make such a study more comprehensive and e.g. investigate reactions in the actual context. The closer one comes to this, the more valuable the results become. It opens up for how broad the area is, how many angles can be used and makes interesting things visible. A number of costs can be spared, when potentials on the business, development and design related areas are sought out and tested in this manner. Weaknesses can be detected and important conditions that must be in place show themselves and thus one can gather important information for optimising of a potential next project. Development of such first prototypes is also extremely important in relation to being able to address problems and possibilities for solutions. Prototypes can be seen as a form of means of communication, a form of mouthpiece for designers and developers, which conveys understanding and development on the field5. Each time a prototype is created, it becomes possible and easier to optimise and increase the value in a product or a service. For example, the company ECTunes has, via sound prototypes, received a good basis for discussions on the problems and possibility for demonstrating what could be future sounds for electric vehicles. In addition, it is collective constructive input for the technology.
Cordy Swope, For Designers Prototyping is a Way of Thinking; International Designcamp 2011, From Intangible to Tangible. From Tangible to Wonderful, 2011; p.66.
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about the individual
// Soundlessness – Opportunities instead of Barriers
The sound projects Sound ’n’ Safe and e sound stem from the same idea, where e sound – how will your electric car sound? is a further development of Sound ’n’ Safe.
Sound ’n’ Safe In the very first project, Sound ’n’ Safe, etrans saw the lack of engine sound as an opportunity instead of a barrier. With electrically powered vehicles it is possible, in principle, to add any sound whatsoever and thus possible to create a more artistic expression. In the project, three students from Vestjysk Musikkonservatorium in Esbjerg developed three different sound tableaus, which were exhibited at COP Kreativ, a predecessor to COP 15 in Copenhagen. For exhibiting the sound tableaus, a vehicle like form was developed with a
steering wheel, pedals and two seats that you could sit in. As a visitor you can, with the aid of buttons, choose to listen to the different sounds. During the course of the first exhibition of the installation it proved that the sound project did not function optimally. Besides problems with the technical part, it becomes clear that the visitors lack a visual feedback so that you get a sense of driving in a car and experience the sound in a form of relevant context. The visitors have difficulty of understanding the sound experience, it is too abstract, and the visual communication of the three sounds is too limited. The sounds are experimental and abstract and very far from engine sounds. In all, it is difficult to awaken the public’s interest for the installation and the problem. There is a need for a more engaging and concrete experience in order for the public to understand and have interest for the problem.
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Photos from Sound ‘n’ Safe, 2009
e Sound – how will your electric Car sound? The subsequent e sound is an interactive installation and a computer based game, developed on the basis of experiences from the first project, where one can create one’s own sound for electric cars and then test both one’s own and other’s sounds on a drive through a virtual landscape. The installation gives users, in a fun and playful way, the opportunity to express wishes and ideas surrounding sound for electric cars. One is engaged and involved in the development of sound, and the goal is to awaken user curiosity surrounding electrically powered vehicles. The idea for the installation is developed by industrial designer AnneMette Clausen and the concept is drafted in co-operation with interaction designer Ole Prinds. The detailed preparations are done in a team comprised of the above named and interaction designers Mads Mosbæk Pedersen and Claus Bjerre Jacobsen. etrans’ partner ECTunes has supplied special speakers for this version of the installation. The immediate goal is to involve and engage the user and provide a fun and positive experience. We will give the visitor a good experience and achieve a large degree of involvement and creativeness in the installation. In that way it will make a greater impression and anchor the experience stronger and, thus it is remembered better6. Behind the goal of involving and engaging stands the goal of creating attention about the specific problem and about electric cars in
general. The installation shall function as a communication platform for electric cars and get the topic on user’s agendas by surprising them with an aspect of electric cars that most Danes don’t know yet.
Engage and involve
In order to achieve this we choose to develop an interactive installation, where we use etrans’ methods to its utmost consequence and give users the opportunity to create sound for electric cars themselves. Through the installation, the user is asked how he/she wants or imagines an electric car should sound. The user becomes a co-creator and a part of the installation. We have chosen to allow people to use their own voices to create sound suggestions. In the early phase of the idea development it was tested how one, with the aid of voice recordings, can create a sound sequence that can be used to simulate a movement through time and space. We quickly found out that we can achieve this with the aid of a loop of voice recordings and often achieve fun and entertaining results. The loop technique becomes the central idea for the sound design and in the installation becomes controlled via the gas pedal. Thus, the loop/sound’s speed and the car’s speed are syncronised and form a direct reflection of each other. The faster one drives, the faster and more distorted the sound loop becomes. This element of distortion and repetition is simple and very effective. For most people, it is very
John Dewey’s thoughts are formulated in relation to children and youths in the 1930‘s USA. The reason why his ideas remain interesting and usable is that Dewey had an eye for what role the motivation plays for the result of the learning. Dewey criticised the traditional school system, because regard was not paid to the child’s own interests, abilities and intentions. 1990s art museums seldom assign the motivation sufficiently great attention. It is important to understand that the scope of what one actually learns in a teaching situation rises proportionally with the degree of the motivation, interest and prior knowledge”. Source: www.cultur.com/1998/980109.html Erfaringspædagogikken; www.da.wikipedia.org/wiki/Erfaringsp%C3%A6dagogik
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Photos from e sound, the proces, 2009-2010
funny to experience their own or other peopleâ€™s voices in this way. At once the desire arises to test other sounds and experiment with the effect in correlation with the car driving.
Structure of the Installation
It is maintained that one, as a user, still must sit down in a car-like form while one uses the installation. In the car, there are now two separate user interfaces, the one is a touch screen that controls the sound recordings and playbacks. The second shows a computer animated car ride. Both user interfaces form visual feedback and amplify the experience of a car ride seen from the interior of a car. The car ride follows a straight road that goes through a smaller city and through a cultivated landscape, where in a certain distance it shifts between day and night. With the aid of a gas pedal and a brake pedal, the user can control the driving speed. We have chosen to remove the steering wheel to focus on the experience on sound. One drives in an eternal loop on the same track. Two half-circular visualisations in the lowest part of the screen show, among others, via green and red colours, how much energy one uses. The green colours stand for the energy savings and environmental friendliness and the red for the aggressive and wasteful. These things are not explained further but are, with the aid of the design, self-explanatory and immediately understandable.
If one wants to record a sound or hear otherâ€™s recordings, then this is done via the touch screen interface. The touch screen solution is chosen to simplify the installationâ€™s use, construction and expression. The interface shows a circular and symmetrical composition of 20 smaller circles that are placed around and connected with a larger circle that forms the centre. When one presses a button in the middle, one starts a sound recording. At the same time, a small web camera takes a picture of the person that makes a sound in the microphone. When the sound is recorded, it appears on the screen as a new circle with the picture of the user. Via the picture-sound files it is easy to orient oneself in the sound library, as one can immediately see who has recorded a sound. At the same time, pictures of the users contribute to making the other sound recordings more interesting and give the user indications of what the sound behind is. By pressing on one of the circular pictures one chooses the associated sound and can test it by pressing on the gas pedal. One can browse through all the sounds that have been recorded and saved in the installation by pressing on the arrow keys in the left and right side of the interface. At the bottom of the page, it is constantly updated how many pages of sound are available.
The Narcissistic Aspect as Motivation
To make the recording of sound more meaningful and visually attractive, the sounds are arranged with the aid of photographs of the persons
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Illustration of the e sound installationâ€™s first set up
Screen shots from the e sound installation.
From the opening of the exhibition e-collection at Illumâ€™s, Copenhagen, 3. December 2009
who have recorded them. In that way people’s appearance becomes a direct representation of the sounds. It also contributes to motivating people both to test sounds and to record sounds. The element speaks to and gives space to most people’s narcissistic side, where we enjoy seeing ourselves and exploring ourselves from the outside7. That the photographs are saved in the installation and that it is more or less publicly accessible add a dimension to the exhibition, in addition to being known in relation to others. This also acts as motivation for many people, among others, because of the modern culture of the famous and celebrated. Some people will choose not to record sounds and have their photograph taken because it does not suit them. But, on the other hand, the picture affects other visitors, as the installation doesn’t seem dangerous and rouses the inborn need to imitate others. The installation places the user in focus and thus becomes more meaningful to the individual. When something is about oneself, most people become interested and attentive. This concept is often used in interaction design8. Indirectly in this way, one receives communicated
topics that are viewed as abstract and immediately uninteresting. In this case we must place electric cars on the agenda. The topic is in the first case secondary to the user: It is the way in which the topic is communicated that makes the installation interesting. Both by saving a picture and your voice being recorded you put your touch on e sound and play a part in creating its content. You become a part of it. This is also a hold that can increase the interest9. The installation is not a game, as it does not contain an element of competition. In that way it has a democratic form, no sound is better than the other. It emphasises play and the experimenter and most who test it express satisfaction and a desire to explore. Many record a whole range of sounds. Often, the user is captured by the play and the challenge of creating a relevant sound for an electric car becomes secondary. In relation to getting electric cars on the agenda this is, however, a good thing, as a more positive experience will create a stronger memory.
The final installation is comprised of a surrounding exterior part and an electronic interior part. The surrounding part is almost solely made of
”In psychology, the term is used to describe both normal self-love and unhealthy self-absorption due to a disturbance in the sense of self.” Kilde: www.en.wikipedia.org/wiki/Narcissism E.g. The technology company Intel has developed a webpage under the name Museum of Me. On the page one can via facebook be presented with a virtual museum experience of one’s own life. www.intel.com/museumofme/r/ 9 John Dewey, see note 1; www.cultur.com/1998/980109.html 8
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The course of recording sounds.
During the opening of the etrans exhibition at Dong Energy, Gentofte, 5th April 2011.
From the the etrans exhibition at TRIN, Kolding, February-April 2012.
Sound ’n’ Safe model
e sound model
e sound lite model
Sound ’n’ Safe user interface
e sound user interface
e sound lite user interface
lightly treated ash and formed so that it reminds you of a vehicle that is inviting to sit in. The front part of the shape, which looks like a bonnet and front window of an average car, is relatively closed and houses the installationâ€™s core, the computer. Oblong thin pieces of wood form an airy and dynamic surface. It seems light and partly open. The mid-section holds two screens, which are placed on top of each other: The top and largest shows the virtual drive, and on the lowest and smaller touch screen the sound recordings and overview over the recorded sounds are controlled, in addition to information about the etrans project and the sound problem. The rear part is open and is comprised of a wide seat where two people can sit and test the installation. Two upward curved laths on both sides of the shape go from the front to the back part and turn the entire object into a cohesive unit. They give the shape dynamics and direction. It is clearly marked where the object begins and ends, and as a user one must step over a low physical barrier to get in and come out.
pressive unit and to accentuate the sustainability and the different. The steering wheel is omitted as it does not have any practical function and thus confuses the user. The interface has also been optimised, among others, with information texts regarding the problem and short sound bites of the chosen sound.
Materials and colour scheme communicate sustainability, harmony with nature and a different vehicle. In the construction, regard has been paid to easy transport and therefore the shape can be separated into three parts that can be carried by 1-2 people and transported in a normal van: The final model is designed and partly conducted by industrial designer Anders Huus.
By far, most sound suggestions do not seem particularly serious or wellthought-through and are characterised by most being enticed by the play. However, it would be interesting to find out if there are any general tendencies in the sounds, which can be used to further develop the sound.
The physical part is continuously being optimised as a result of experiences with users. The original version was created in a very short time and here the platform element is accentuated (see picture of the first simulator). The car shape is very simple and angular, as at that point in time it was most important to have it built as fast as possible. The dominating colours are white, with elements of black and light green. Race car seats and a race car steering wheel create the primary illusion of the car. These elements are later removed to create a stronger ex-
The e sound installation tries to simulate the experience of a drive in an electric car with an artificial engine sound. The design means that one is conscious of there being an artificial world, together with one gaining an impression of how our perception of electric cars, streets and roads can change via new sounds. The user often seems well entertained and involved in the installation. For some it can be a challenge to find a sound and it is clear that children, youths and men are more attracted by the installation than women and the elderly.
The installation lacks being more self-explanatory about how it is used and about electric cars in general. Therefore, in some cases, it is doubtful whether the users go home with the intended goal of getting electric cars on the agenda. Via the installationâ€™s design it is, however, successful in involving the user in the development of sound and as it is desired in a user driven method, they are allowed to express themselves in the most literal sense and through their picture and sound becoming part of it. To date, more than 1,000 sounds have been recorded.
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The Sound ’n’ Safe II Project: user driven Design/ Innovation and Technical Requirements in Harmony Sound ’n’ safe II is a further development of etrans’ work with electric car sound. In this project, prototypes of external sounds were developed for electrically powered motorcycles and buses with user driven innovation and design as a method and in co-operation with the partner ECTunes and sound designer Yann Coppier. The project also has the intention of getting the discussion surrounding electrically powered vehicles started and drawing attention to the problem. The project will attempt to demonstrate what design and the user driven method in combination with each other can contribute where innovation is concerned in more or less technical areas. We feel that a sound designer on the expressive plan will be able to contribute with a different suggestion than a sound engineer. The electric car sounds that currently exist on the market sound like each other and, according to Yann Coppier, show two tendencies: Futuristic turbine sound and sound that remind you of a mobile telephone’s ringtones10. Some refreshing input is lacking.
Sound is only activated when starting the Car and at low Speed In Sound’n’Safe II, the idea is to develop artificial car sounds that are only activated when the car starts and at low speeds. ECTunes directionally determined audio equipment furthermore ensures that the noise pollution is reduced to a minimum by only sending out sound in certain areas in the front and behind the vehicle, where there is the need for it.
Introducing the User-driven Method
During the sound project, representatively selected persons were asked about the sounds and their response has played a role in determining the final design of the sounds. Due to the short duration of the project and because in this context the goal is to get people’s opinions about and perception of the sounds through these tests, these are carried out as quantitative user surveys11. By involving users in the development of sounds and using user-driven innovation as a method, we will ensure that the product is optimised and targeted towards the target group, thereby increasing the accuracy. It seems obvious to ask and involve the persons in the development process, which in the end will use the product12.
Among others, the following electric car models are available with artificial engine sounds and follow the pattern described above: Ford Focus, Toyota Prius, Nissan Leaf, Halosonic Lotus. Qualitative user survery: “The qualitative survery methods aim at depth ahead of quantity of infomation and play a role in understanding people’s attitudes and gaining an insight into their motives and feelings. The method can give greater insight into what people actually mean, but that is not necessarily the opinion they will give in a telephone interview”. Source: Scharling Research: www.webbyen.dk/vishjemmeside.asp?mode=top_frame&id=373190&side=&webside=5725 Qualitative brings produces new perceptions that designers can work with. In relation to this, they will show the same results as quantitative studies but in a shorter time and with fewer resources. Therefore, qualitative studies are to be preferred in this context. Source: kvalitativmetod.webs.com/ and www.leduc.se/metod/Kvantitativochkvalitativmetod.html. It is recommended to have at least five and max. eight persons in a qualitative test and it is sufficient to test 6-12 users to identify more than 90% of a concept’s errors. Source : www.useit.com, www.doblingroup.com 11
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A regular shift between development, testing and adaption of sound. We choose to look at electrically powered buses and motorcycles, as these have so far not had much attention in the sound debate. Especially a public means of transport, such as a bus, will be able to reach many people and create attention around the problem. In addition, we find out in the etrans project’s first year that electric buses in Copenhagen drive very carefully, as pedestrians and cyclists do not notice them on the more quiet roads. In that way, there is also a concrete problem in Denmark that we can grab hold of and test on. In addition, we hope that unusual electrically powered vehicles will create interest and attention in the press and with ECTunes’ potential customers.
Structure of the Project
The project is relatively short and intensive: The development of sound takes place over approx. 25 days in the autumn of 2011. The concrete goal is to develop three complete soundscapes for electric buses and
three for electric motorcycles, which can be used in ECTunes’ technical equipment13. In a short period of time, we will create sound that is different and creates debates, but that is also close to the user’s wishes. The overall construction of the project consists of a regular shift between development, testing and adaptation of sound. In this way, the sounds can be optimised at the same time as we regularly target ourselves sharper toward the user. An introductory research and knowledge exchange is performed between the team members, especially in relation to what sounds currently exist for electrically powered vehicles.
The Project’s Framework
The framework for the development of sounds is, on the technical side, set up in agreement with a White Paper, which ECTunes has drafted together with a number of businesses14. The overall goal is to achieve safety for the soft road users with sound that is reduced to a minimum.
12 User-driven innovation: “…takes a point of departure in the customer and it is the expectation and desire to fulfil a customer need, in a better way than before that drives innovation”, Rosted, J., Brugerdreven Innovation, Resultater & Anbefalinger, FORA, Økonomi og Erhvervsministeriet, 2005; p.10. ”If companies in a systematic and scientific method investigate customer needs and use customer needs that as of yet are undiscovered as sources of innovation, the innovation process is designated as BDI”, Rosted, 2005, page 34. ”The used methods span broadly from customer interviews over targeted market analyses to scientific analyses. The analyses are described as ethnographic and scientific studies, questionnaires, observation, personal interview, with results that are evaluated in the light of societal and cultural developmental tendencies.” Source: Design’s role in User-driven Innovation, Master’s thesis, Mette Mikkelsen, 2009, page 10. If the goal is “…to uncover and use knowledge of how users shop, experience and think, that is to say, cultural knowledge, to help companies by creating, implementing and evaluating the right products and services. I.e. products and services, that have so much value for users that they cannot help but adopt them. User-driven innovation is thus mainly about hitting the market right, and about minimising the business risk.” Source: Anthropologist and user consultant Katja Øder Hansen, 1508 A/S; www.kommunikationsforening.dk/Menu/Fagligt+nyt/Artikler/Hvad+er+brugerdreven+innovation%3F 13 In this context, a soundscape is understood as being a set of expressionistic coherent sounds, which will replace engine sound. IN this case, it is a startup sound, an idling sound, a reversing sound, an accelleration sound and a charging sound. For the electric motorcycle the reversing sound is irrelevant. 14 White paper on external warning sounds for electric cars - Recommendations and guidelines, Financed by Danish Sound Technology Network, AV 1224/10, Project no.: A520040, Page 1 of 65 incl.11 appendices, 31 March 2011, Contributers DELTA SenseLab, ECTunes, Sonic Minds, 1iCapture.
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Sound ‘n’Safe II: Time Schedule and structure of the Project 6th Sept.-11th Nov. 2011
Finalization of Sound Scapes Adjustment, Optimization and Development
Adjustment, Optimization and Development
Disposition of Project Frame
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For example, according to the White Paper report, the sounds must be between 200-2000 kHz. Thus, the deep bass tones are avoided that can go through house walls and disturb people that live close to trafficked roads. The sound must, on the expressionistic side, be reasonably recognisable as a vehicle but not necessarily alarming. The White Paper report recommends a pulsating sound that is perceived by most as something that is in motion and thereby creates attention. It is important that people on the street will immediately associate the sound with a vehicle, as one otherwise does not perceive it as something that has significance to one’s safe journey on the street. Expressionistic parameters are also set for the sounds. The sound suggestions shall take a point of departure in three categories: • old school / mechanical sound • natural/organic • culture/ abstract sound with inspiration from art, film, music. At the same time, the sounds must mutually range from a relatively traditional and known sound over a more experimental to a futuristic sound. These parameters have been chosen based upon an experience that has a constructive effect in being able to work with expression that constitutes a contrast in relation to each other.
Traditional or recognisable expression is chosen because most people can best relate to something that they can recognise and know what it involves. Nature and the organic are chosen because the subject area of electric vehicles is associated with sustainability and greener and environmentally correct behaviour. The futuristic and completely unknown expression will play a role in creating debate and show what could be a possible future scenario.
First user Survey
For the first user test, ten sounds were developed for electric buses and ten for electric motorcycles. The qualitative user survey was carried out on two teams of test participants with six-seven people on each team. Parti-cipants are selected so that they cover both sexes and different age groups (within 22-65 years) and backgrounds. A test is also carried out with six visually impaired people aged 32-8715. The reason is that visually impaired people in this connection are a particularly vulnerable target group who must be taken into account. They are often completely dependent upon their hearing in traffic and electric cars can be extremely dangerous to them because they are so quiet. Their perception of the auditive world is often more well-developed than those with normal sight, and it is important and valuable to have their feedback included in our survey. The test is carried out at the Kolding School of Design in a smaller and relatively neutral appearing room with tables, chairs and a music system.
This test is carried out so that each participant is assigned an assistant who reads the individual questions from the questionnaire and writes down the participant’s answer.
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The room is furnished with carpets and pillows to achieve good acoustics. The survey lasts approx. 50 minutes and takes place in such a way that all of the team’s participants sit around one table. An idling sound is played, after which a question is to be answered on the questionnaire handed out. The first part of the test is a so-called blind test, that is to say, participants are not told what the sound will be used for and sounds that are set for electric buses and electric motorcycles are mixed up when played. This is done to find out how the sounds are perceived out of context. In another part of the test, the same sounds are played again, but this time participants are told which vehicle they will be used for and they are each played back in their own category. The sounds are also played now with acceleration like sequence to investigate whether the sounds are perceived as accelerating. This is important to communicate that the sound comes from an object that is in motion. In the first test the team decides to investigate the following five aspects of the sound suggestions: • associations • irritation • if they are perceived as positive, negative or neutral • suitability in relation to the vehicle (among others, size) • perception of acceleration. The questionnaire is designed so that it is easy to understand, both in relation to the language and the visual communication. In most
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questions, the participant must place a tick on a scale or select an object or a symbol. This makes the reading easier for the participant and the answers are subsequently more unequivocal.
Results from the first User Survey
The results from the first test are visualised in three different diagrams (see diagrams with the different questions). The analysis of the answers shows that the users perceive the majority of the sounds as dark and heavy and that they prefer melodic and light sounds. Sought for are ”green”, light and happy sounds that can tell something about the positive sustainability of an electric car and symbolise a new world and a new product. Most users find sounds that sound like intense acceleration to be irritating. The visually impaired sought for sounds that sound like normal car engine sounds as they can immediately understand these. They must be able to ”read” a great deal of information based on a sound, e.g. the type of vehicle, size, direction, etc., therefore the sound is more decisive for them than for non-visually impaired persons. Based upon the answers a top five list was drafted for each vehicle category. The three most popular sounds from bus and motorcycle sounds were taken further to the next development phase and test round. From each category, a sound was also selected that showed an interesting connection, e.g. a sound that an overwhelming number of participants perceive as scooter/motorcycle-like. Furthermore, for the next test a completely new sound will be developed that take up some of the participant’s questions.
User tests, 6. Oktober 2011.
User forSound Soundfor for Electric Vehicles User Test Test for Electric Vehicles 3. Answer in the following three areas after a sound has been played:
3a. Irritation: Imagine you live on a trafficked road or next to a parking area. How irritating is the played sound? Put a mark next to the one that corresponds with your experience.
3b. Acceleration: How powerful do you experience the acceleration in the played sound? Put a mark next to the one that corresponds with your experience.
3c. Match: How well does the played sound fit the vehicle? Put a mark next to the one that corresponds with your experience.
Extremely 10 irritating
Powerful 10 acceleration
Medium 5 acceleration
A little irritating
Fits a little
Not irritating/ pleasant 0
No acceleration 0 1.
Does not fit at all 0
4/4 www.etrans.dk // October 2011
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Analysis Diagrams of the first User Test
Analysis of qualitative user test of sounds for EVs – team I-III
Analysis of qualitative user test of sounds for EVs – team I-III
Analysis of qualitative user test of sounds for EVs – team I-III
Number of participants: 19
3a. Irritation / annoyance // electric bus sound sketches: Imagine you live on a trafficked road or next to a parking area. How irritating is the played sound to you? Put a mark next to the one that corresponds with your experience. Number of replies: 14 + 5
Question 1b: Which vehicle did you hear when listening to the played sound? Answer by marking the vehicle that you think the sound fits.
Visually impaired hereof: 5
Question 1a. What is your immediate impression of the sound? Positive, neutral, negative? Please note the order of the sounds has changed. Sound
M7 Piano idle
M10 Forge Limit
= a choice
B5 Clusters 5 idle
M7 Piano idle
Extremely 10 irritating M8 Pulse 1 idle
B3 Drones 4 idle
M1 Tuva idle
Very irritating 4
B4 Interval 1 idle
M6 Clusters 2 idle
B10 Andreas Speed idle
A little irritating 2
M5 Forge Limit 2 idle 10.
B2 Bleng 2 idle
Not irritating/ pleasant
M4 Wind idle
B1 Melodic Bus
B2 Bleng 2 idle
B3 Drones 4 idle
B4 Interval 1 idle
B5 Clusters 5 idle
B6 Melodic Drone 1 idle
B7 VesterH2 idle
8. B8 Beleng D idle
B9 Clusters 3 idle
B10 Andreas Sp
Number of choises
15 + 5
M10 Forge Limit
B5 Clusters 5 idle
15 + 4
M8 Pulse 1 idle
13 + 4
B3 Drones 4 idle
14 + 4
M1 Tuva idle
B4 Interval 1 idle
= a choice from a visually impaired person
Please note: There is a changing number of choices as some of the participants chose to choose several vehicles while others in some cases omitted to choose.
M6 Clusters 2 idle
14 + 4
B10 Andreas Sp
M5 Forge 10. Limit 2 idle
13 17 + 6
Anne-Mette Clausen // etrans // 22.October 2011
Anne-Mette Clausen // etrans // 22.October 2011
Anne-Mette Clausen // etrans // 22.October 2011
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Second User Survey
After the next development phase, there are five sounds for buses and five for motorcycles that are tested in the second user survey. The optimal would be to investigate the sounds out in the traffic in the context they will be used in. As this is, however, impossible at this point of time, we choose instead to film these vehicles, set the different sounds in during video editing and demonstrate these to the test participants. In this way, we also show them in context. We have ensured that the vehicles both speed up and slowdown in both demonstrations so one experiences a drive with a change in speed. First, we show them a video of the same sequence, but with the original sound so that one can gain an impression of the vehicle’s soundlessness. For the motorcycle sounds, we have also made a short video demonstrating the danger of soundlessness. These things will give participants an impression of the problem. The survey is carried out on ten persons between the ages of 22-64 with different sexes and backgrounds. It was carried out at Kolding School of Design among people who have an association with the school. They see the videos on a computer with headphones and are handed out a questionnaire (front page/screenshot of video + page from the questionnaire). They are instructed in the use of the computer and the questions and left alone while they carry out the test. The test lasts approx. 10-15 minutes and asks four questions for each sound.
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The questions deal with: • how pleasant the sound is perceived as being • how well it suits the vehicle • if acceleration and stopping are experienced • allocation of a collective grade for each sound Here, the goal is to come up with a reasonably pleasant sound that, at the same time, communicates with a certain type of vehicle and movement.
Results from the Second User Survey
The user survey showed this time that participants prefer sounds that are closest to something recognisable, and that have a relatively easy and light expression. It also seems that it is easier to create a comfortable and reliable sound for buses than for motorcycles. This can be due to the motorcycle’s sound for the test participants being closely associated with an acceleration-like sound, which is also perceived as irritating. Thus, it makes it difficult to create a pleasant sound that still owns enough acceleration to be able to be perceived as belonging to a motorcycle. The three most popular sounds from each category are refined, and a complete soundscape is designed for each that can be used in ECTunes’ sound equipment. The project is thereby carried out. All the sound designs are compiled with a video showing the context and
User Test for Sound for Electric Vehicles
1. How pleasant do you experience the sound? Put a mark.
not at all
2. How well does the sound match the vehicle? Put a mark.
3. How explicit does the sound communicate acceleration and halt? Put a mark.
4. In relation question 1-3 how high would you rate the sound? 1 is the lowest and 10 is the highest grade. Put a mark.
www.etrans.dk // November 2011
The second user survey.
The greatest challenge in testing sound on laymen is that for most it is difficult and they are unfamiliar with expressing themselves about sound. Added to this is the fact that sound is fluid and immaterial and difficult to capture, even if it is heard several times.
Shooting the videos that will demonstrate the sounds in their context.
In the first tests the participants became mentally tired and had difficulties absorbing the many impressions. how the vehicle sounds without sound. The intention is to give users the opportunity to gain an impression of how it functions and is experienced and to mutually compare them. These are placed on the etrans project’s website with free access for all.
Conclusion of the Project and Methods
In the project Sound’n’Safe II two sets of soundscapes were developed in a relatively short period of time to two very different electrically powered vehicles and quite a bit of experience was gathered in different areas.
Experiences with the Test Method’s Practice
In relation to the qualitative test method it seems as if it is an advantage to be able to test sound for two completely different vehicles in the same test. It’s easier for participants to relate to sounds, partly because there is talk of completely different properties, for example, buses are very large and heavy vehicles in relation to motorcycles. One should be aware that participants can influence each other during the test, if talking out loud about choices and attitudes is permitted. The test form itself with questionnaires, where each participant relatively anonymously can complete the questions functions well and makes this possible. With regard to the number of sounds in the test it is viewed as being too extensive to test 20 sounds (ten for motorcycles and ten for buses)
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in two rounds per survey. The purpose was to present participants with a reasonable different natured selection of sounds, but in the course of the first tests it seemed as though participants became mentally tired and had difficulties absorbing the many impressions. With the high number of sounds it is difficult in the long run to differentiate sounds and keep the concentration. It functioned better in the second test round, where there is two sets of five sounds, that is to say, ten sounds in all that were tested. This number is more manageable and suitable. The questions have mainly closed answer possibilities, where one can cross out or select one or more possible answers. Naturally, it limits the breadth in the answers people give, but instead it makes it easier to get an overall picture of the tendencies in the sound suggestions. We can see, that the greatest challenge in testing sound on laymen is that for most it is difficult and they are unfamiliar with expressing themselves about sound. Added to this is the fact that sound is fluid and immaterial and difficult to capture, even if it is heard several times. If one was to give completely open answer possibilities, it would be a challenge for test persons to express how they perceive sounds. An improved idea could be that one, in a previous test, collects words that describe the sounds and uses these in the questionnaire. In that way one could develop a vocabulary and make it easier for participants
Electric bus in the centre of Copenhagen.
Developing sounds in the studio
to express themselves surrounding sounds. The disadvantage with this, as opposed to a completely open question, is that by naming the vehicle types one must choose between, one sort of puts words into the mouths of the participants and limits their opportunities for making their own statements. To ensure that participants in the user test understand the intention of the test and each question, it is necessary to explain in as simple and clear language as possible and to repeat this during the test. If one only explains one time, it is not certain that participants understand what they must answer and one risks the test giving an incorrect picture of what participants mean. This becomes clear during the first test round. It is important to be conscious that it is impossible to create completely neutral circumstances surrounding a user test. Everything from the surroundings the test is carried out in for the participants, the test layout itself and the sound’s mutual context has significance to how one perceives each sound. In the last part of the project, it is also very clear how much it means to experience sound in the context it is intended. Something could suggest that people have an easier time accepting innovative sounds, as soon as they are displayed together with their ”owner” and are close to the actual usage situation. In addition it seems to be decisive to come close to an actual scenario in order to be able to judge the experience of the sounds with certainty.
User-driven versus Innovation
In the project we have set ourselves the goal of being innovative and
creating debate based upon the users’ answers from the surveys. During the course of the user surveys it showed, however, that participants are quite conservative in their choices and that they prefer what they know or something that is like what is known and safe. That is to say that there are only a few surprises in the results from the user tests, which could point in the direction of a more innovative solution. This indicates that the user-driven does not necessarily involve innovation and one can raise the question whether it is at all possible to create innovation solely via users? In this case it seems that the userdriven and innovation work against each other. We choose to go down a middle road, where we both pay regard to the results from the studies, but also to other tendencies and contexts seen in a design related perspective. In practice it occurs by us taking the sounds along that the users have ”chosen” but also working further with a couple they have not chosen, but that we think work well and are innovative. The reason why we choose this way is that BDI, to a high degree can contribute to the product development but it is no guarantee or innovation ”pusher”. Users cannot alone create innovation. There must be one who can interpret them deeper than simply the immediate statement. Therefore, a combination of user-driven and design driven innovation is an advantage. The user-driven ensures that one comes close to expression and needs that are relevant to the user. The designer can ensure the new creation that is necessary to bring new and better solutions into play. Without the user-driven, one risks creating products and services that are far from what users will adopt or can live with.
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The test paints a picture of what sounds they are most willing to accept.
The Project’s Limitations
The project has been timewise relatively limited, which means that there has not been time to carry out user studies that extend over a longer period of time and provide the opportunity to investigate the user’s relationship to sounds over time. Innovative or new things require getting used to and people are quite good at getting used to new things, but it requires time. Testing the same sound over a longer period of time could, perhaps, have reflected another preference. What our test shows is whether users like these sounds at a given point in time. The test, therefore, paints a picture of what sounds they are most willing to accept. The final sound suggestion represents a compromise and is ”most advanced yet acceptable”, such as the designer Raymond Loewy recommends it. Another limitation is the technical equipment that the sounds are to be developed for and played through.
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During the first part of the process it became clear that the technical equipment puts limits to the sound related freedom of expression in an unsuitable degree and to a larger extend than first anticipated. Concretely, this means that the sounds are distorted in unpredictable and undesired directions. The quality is reduced and the expression becomes far from what was the intention. Light and easy expression that the users sought-after can only be created to a small degree. It makes it difficult to satisfy users’ and our own requirements and suddenly we stand there with a challenge that is more about technology than about expression and experience and that ties our hands, so that the innovation is significantly limited. Therefore, a central acknowledgement from the project is that if one wants to create innovative solutions, then one must be very aware of how much the technology must determine the parameters for what can be done.
It can immediately be seen as an advantage that the noise level drops, but it also involves a radically different way of navigating, when one cannot hear oneâ€™s fellow motorists in the same way as now.
In the project, three levels are linked: the user, technology and design. The challenge is to allow all three to play a role and that none takes the control Mette Mikkelsen, project manager etrans.
The Sound’n’Safe III Project: Brave New Sounds The purpose of the Sound’n’Safe III project is to create new and creative sounds, intended for electric motorcycles and electric buses, which interactively react to the driver’s handling of the vehicle’s speeds and gear system.
The project comes into existence based upon the experiences we gained in the previous project. It is partly a reaction to the technology representing a relatively large limitation in relation to the artistic development. But the users’ statements also limit the innovation. In this project, we primarily work with a design driven method in order to be able to give the creativity a bit freer rein. However, the statements, results, reflections and experiences from the user surveys are taken down and carried along, as they can be helpful by giving indications of how people react to sounds. The goal is to give new angles to sound and provide ideas as to how our future electrically powered vehicles, urban space and thus our world can be. We will show what design driven innovation can do in relation to creating new experiences and new products that, among others, differ markedly in their expression from what we know and what we envisage. We will develop two sets of sound designs with three sounds for electric motorcycles and three for electric buses. We choose the same types of vehicles to directly be able to use experiences from before and in order to be able to compare results and the experience. In their expression, the sounds shall clearly differentiate from the expected and already existing sounds for electrically powered cars. They shall be creative, experimental and a development of new directions and possibilities The
technical requirements from Sound’n’Safe II and the three inspirational areas is retained from the previous project. In that way some clear parameters are kept, which the sound designer can work within. In addition, the following requirements are set for each of the three sounds: • a recognisable sound, that is to say, recognisable as an engine sound from a vehicle • a partly recognisable sound such as a mixture of known and unknown sounds • a non-concrete recognisable sound The intention is to arrive at three completely different expressions that go from something people can recognise, to something that is partly recognisable, to something completely new and unheard. We will reflect the habituation and development process in the users, as well as also providing opportunities for contrasts that one can compare with. Thus, the understanding and the experience of the expressions is encouraged. The final sound designs must have high technical quality where the spectrum of details and frequencies are concerned, that is to say, fuller sound.
The sound designer chooses this time to create sound systems instead of soundscapes. That is to say, each sound design is created as an individual system that builds on synthesis. The idea is that the sound systems actively react to how speeds and gears are handled, like that which happens inside a petrol powered engine creating sound. In that way one can create interactive and living sounds where each sound produced will almost be unique. The sounds will, to a higher degree, be able to directly
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reflect how ’green’ you are in your driving style and to a certain degree, your mood/character just as with a normal car. With these sound systems the vehicle’s auditory expression becomes more dynamic and active. Each sound system is constructed according to different principles, e.g. an additive principle. This also contributes to creating greater variation. Soundscapes from Sound’n’Safe II are, in comparison to this, fixed sounds based on finished sound files that are simply regulated at playback speed depending on how one presses the gas pedal.
A decision is made as to how the requirements set up are combined. Yann Coppier : Choices Bus Recognizable
Sound designer Yann Coppier, Studio Ovale describes the limits like this16: Creating a library: sound possibilities • Categories / themes & coherence • Recognizable / Abstract • Movement / No movement • If yes, regular / irregular movement • Regular movement can be pulse or rhythm • Movement can appear on the pitch, in the amplitude, in the frequential domain, in the time domain • The content can be tonal or atonal. Annoyance is the key here. • How to create agressive or soft engines link to the product. • Adding a green/sustainable touch. 16
Recognizable Experimental Unknown
Process related rules are drawn up and it is decided how work shall be done with the development of the sounds and what aspects they shall otherwise fulfil.
From “Feedback on the etrans project (sound design part)” by sound designer Yann Coppier, Studio Ovale. The entire description is found in the report.
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As a point of departure, a library of sound is created that builds upon the topic parameters. These are used as a guide to develop different auditory expressions.
The technical equipment for sound in electric vehicles
A car’s sound reveals something about speed and acceleration and the sound plays a role in giving the driver and fellow motorists a sense of the car’s speed. Without sound one will miss an important indicator and as driver of the car one may also possibly miss the car’s auditory response during e.g. acceleration.
Yann Coppier: Decisions • Use of synthesizers for constantly evolving sounds. • Additive synthesis: analysis/resynthesis/Phase vocoding/Granular synthesis/Convolution. All these methods allow to use changes in the pitch without altering the tempo, and vice versa. They also allow for considerable possibilities in terms of sonic manipulations. The different sound system are given the following names and have these technical backgrounds: For electrical buses: • Mechanical Abstraction; recognisable sound, mechanical. FM synthesis, 4 operators • Untamed Nature, partially recognisable sound, nature/organic, granular synthesis, 8 sampled oscillators • Animal Evolution; unknown sound, nature/organic; subtracting synthesis, 5 oscillators. Coppier’s description of the different sound systems: Bus 1 – “Mechanical Abstraction”. Recognizable sound, mechanic. FM Synthesis, 4 operators. All kinds of strange movements will be shown here. From unearthly vibrations, to quite familiar engine-like features. The sound should change depending on a lot of factors, like you’d find in a sound installation. Those factors will be speed, acceleration, angle of bending towards the ground (for a motorcycle), nervosity of the driver and presence (or not) of other engines around. When the engine is idle the sound will be humming.
Bus 2 – “Untamed Nature”. Partly recognizable, natural/organic. Granular synthesis, 8 sampled oscillators. The overall sound at regular speed will be pleasing. Speed will be shown by an increasing amount of elements / animals in the sound. Then acceleration will make the sounds explode more or less violently depending on how strong it is, like accelerated neutrinos with small particles of sound moving fast around itself. When the engine stops, the only sound is an insect at night. Bus 3 - “Animal evolution”. Unknown sound, natural/organic. Subtractive synthesis, 5 oscillators. Two arms sweeping the floor in the front front, like a beetle’s mouth. Kind of organic wheels on the side, independent but quite similar to each other. When the bus turns on the right, the right side goes faster and the left side goes slower. In the middle, a kind of centipede is running. When the bus stops the animal is breathing/resting. Electric motorcycles: • Perpetual Movement Illusion; recognisable sound, traditional/ mechanical; additive synthesis, 10 oscillators • Exploring Space; partially recognisable sounds, cultural/ abstract; spectral synthesis, 96 oscillators. • Sea Travellers; unknown sound, natural/ organic; enveloping, 12 sound landscapes. Motorbike 1 – “Perpetual movement illusion”. Recognizable sound, old school/mechanic. Additive synthesis, 10 oscillators. A constantly evolving sound, up (forward) or down (backwards). The speed is shown by the width of the pattern (more or less up and down), while acceleration is shown by its speed. When slowing down and ultimately stopping the sound will end up on an foggy note.
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Motorbike 2 – “Exploring space”. Partly recognizable sound, cultural/abstract. Spectral synthesis, 96 oscillators. A stable engine will make you hear a subtle ever-changing spectral loop (won’t include beats for the moment, to avoid annoyance). Any acceleration or slow down will disturb the loop, inducing changes in its structure and stability. When the engine starts or stops the sound will be very close to a DJ scratch. Then the idle sound is always the same, spatial pattern. A few stars pop in from time to time. Motorbike 3 – “Sea travellers”. Unknown sound, nature/organic. Convolution, 12 soundscapes. The way the engine is driven will make it sound like different types of seas. Waves will come when the driver breaks for instance, and if he’s driving agressively and fast he’ll create a storm. The idle sound will be of gentle waves arriving ashore. The technique used will still make the sounds hardly recognizable, apart from the liquid feel. Most of the movement within the sound will come from the acceleration/slow down. Regular speed will leave you in one type of sea, from calm to angry.
An interactive Installation
To demonstrate the sounds and give an impression of the systems, a video installation is developed. All sound designs are placed on the earlier video clip of electrically powered vehicles. The videos themselves are colour adjusted so the colours are intensified. An approx.2.5m x 1.5 m large projection of the videos gives the perception of being in an urban space. The videos show buses and motorcycles in a fixed order and an infinite loop.
The project has been successful in creating some completely new sounds that do not sound like anything existing on the market and that change the vehicle’s expression significantly. There has been relatively
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good space for creativity and the technology has had the task of supporting and expressing what is desired. One can clearly sense how the entire experience of the urban picture can be moved in another direction via the sound. The sounds raise the question of how vehicles may sound, what we will accept and how we will shape our future. But, they also open the door to totally new possibilities and scenarios, where a complete fairy-tale landscape is built up before our very eyes. The most experimental sound makes it clear that cars of the future can sound like anything at all, sound and identity can more or less be separated, and new combinations can be created that will result in completely new experiences. Here, design can play a part in creating our world. As in the previous project, here there is yet an even higher degree of intent to create prototypes that can rouse debate and put the problem on the agenda. One experience is that having a concrete sound design in front of oneself makes it easier to discuss and relate to things, than if people must imagine that there is a completely new artificial sound to a vehicle. Here, prototypes are extremely effective. The sound systems’ abilities to give electrically powered vehicles another identity than sound files can. They assign them unpredictability and introduce greater elements of personality. In order to investigate the full effect of them there is the need for being able to test them in a way where one can simulate the effect of the gas pedal. This could, for example, occur via the installation from the e sound project. Experience the sound designs at www.etrans.dk/soundnsafeIIandIII/
Sound’n’Safe III video installation
// Silent Hybrids and Electric Cars affect Traffic Safety, by Thomas Gadegaard, Director and Founder of ECTunes ApS The silent operation of electric cars may have an effect on traffic safety especially to the blind and visually-impaired, because hybrid or electric cars are less likely to be noticed in traffic. Pedestrians and bicyclists partly rely on auditory cues, why the approach of silent vehicles may not be noticed in time, especially when these vehicles are out of eye-range. Such situations may occur in parking lots and at low speeds up to 25 km/h but also at crossings or exits. In the USA an analysis of crash records has shown that hybrid cars are involved relatively more often in crashes with pedestrians and bicyclists than conventional cars17. A lower noise emission means that pedestrians and bicyclists will perceive cars outside their field of vision later. As the time between auditory perception and avoiding possible contact will be reduced, there is less time for anticipating. In order to get an indication of the influence of the absence of engine noise, RVIM in the Netherlands has calculated the reaction time for speeds between 15 and 40 km/h. If assumed a background noise of 60 dB to be normal in urban situations, the reaction time for conventional passenger cars will be 1.6 s at 15 km/h.
In absence of engine noise, with only tyre-road noise remaining, the response time is halved to 0.7 s. At 25 km/h the respective values are 1.4 s versus 0.9 s, while at 40 km/h 1.4 s and 1.2 s is found. Obviously, the difference vanishes with higher speeds as tire and wind noise increases18. Recent research has shown an increased rate of accidents involving pedestrian and cyclists for electrical and hybrid cars in electrical mode at low speeds when tire noise is insufficient for the car to be heard19. Anecdotal information from drivers of electric cars confirms that observation. This indicates that the need for methods that conveys information about the vehicle and its maneuvers is essential for pedestrians and cyclists20. It is a paradox that the most obvious solution for this problem is to add an artificial â€œmotor soundâ€? or other suitable warning sounds when one of the appreciated advantages of electric vehicles is less noise pollution21. It should be noted that there has been criticism of the need for external warning sounds. It is shown that also ICE vehicles may
RIVM Report 2010: Effect of electric cars on traffic noise and safety RIVM Report 2010: Effect of electric cars on traffic noise and safety 19 National Highway Traffic Safety Administration: Incidence of Pedestrian and Bicyclist Crashes by Electric Passenger Vehicles. Technical report. September 2009 20 National Highway Traffic Safety Administration: Quieter Cars and the Safety of Blind Pedestrians: Phase I Report DOT HS 811 304. April 2010 21 RIVM Report 2010: Effect of electric cars on traffic noise and safety 18
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be so quiet that they are not audible in noisy cities and it claimed that that has not been a specific problem. In reference it is found that blind persons only rely on their hearing, when they are not in noisy surroundings22. From this it can be concluded that warning sounds will help minimizing the risk even if they are not more audible than ICE vehicles and that the warning sounds do not need to be so loud that they are audible under all circumstances. The important challenge is to optimize the signals for maximum pedestrian and cyclist safety with minimal environmental noise and annoyance. One of the tools for minimizing annoyance is to send out noise in the relevant direction (e.g. mainly forward or backward) only. Another tool is to turn down the sound at speeds above 20-30 km/h where the tire noise is sufficient and finally not to make the signals louder than necessary. It is not required that the signals shall be audible under all circumstances, but as a first step they shall be as audible as the noise from ordinary (with internal combustion engines) cars. The tire noise is the same for electrical vehicles and ordinary cars, so the signals shall basically be as audible as the noise from the combustion engine. A next and more intelligent step will be to optimize the signals by making them adaptive to the background noise and/or making them adaptive situation to the surroundings (e.g. only turned on where vehicles, pedestrians and
other road users are co-mingled). This will at the same time decrease the noise pollution and make the signals audible when needed.
Since 2009 the Japanese government, the U.S. Congress and the European Commission are exploring legislation to establish a minimum level of sound for electric and hybrid electric vehicles when operating in electric mode, so that blind people and other pedestrians and cyclists can hear them coming and detect from which direction they are approaching. In January 2010 the Ministry of Land, Infrastructure, Transport and Tourism in Japan issued guidelines for hybrid and other near-silent vehicles. It is found that warning sounds with similar characteristics as engine sounds are the best counter measures against these risksâ€™23. Legislation is expected to be in effect by end of 2012. In January 2011 President Barack Obama signed The Pedestrian Safety Enhancement Act of 2010 making the National Highway Traffic Safety Administration to conduct a rulemaking to establish a Federal motor vehicle safety standard requiring an alert sound for pedestrians to be emitted by all types of motor vehicles or hybrid vehicles (EVs and HVs). Thus, the covered types of vehicles include not only light vehicles (passenger cars, vans, sport utility vehicles and pickup trucks), but also
National Highway Traffic Safety Administration: Quieter Cars and the Safety of Blind Pedestrians: Phase I Report DOT HS 811 304. April 2010 National Highway Traffic Safety Administration: Quieter Cars and the Safety of Blind Pedestrians: Phase I Report DOT HS 811 304. April 2010
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But why equip the otherwise silent electric car with an artificial ’noise pollutant’? Because etrans’ studies have revealed that the lack of an engine sound from electric cars creates fear and opposition against the car in some groups.
A complete replacement with EV’s will reduce the noise level in cities with 3-4 dB. low speed vehicles, motorcycles, medium and heavy trucks and buses. The rulemaking must be initiated not later than 18 months after the date of enactment of the Pedestrian Safety Act. The implementation starts in 2014 and will be effect by 201724. The Pedestrian Safety Act specifies several requirements regarding the performance of the alert sound to enable pedestrians to discern the operation of motor vehicles. First, the alert sound must be sufficient to allow a pedestrian to reasonably detect a nearby EV or HV operating at constant speed, accelerating, decelerating and operating in any other critical scenarios. Second, it must reflect the minimum sound level emitted by a motor vehicle that is necessary to allow visually-impaired and other pedestrians to reasonably detect a nearby EV or HV operating below the cross-over speed. Third, it must reflect the performance requirements necessary to ensure that each vehicles alert sound is recognizable to pedestrians as that of a motor vehicle in operation. In 2011 the European Commission drafted a guideline for Acoustic Vehicle Alerting Systems. The guideline is intended to present recom-
www.nhtsa.gov/staticfiles/rulemaking/pdf/QuietCar-noi-draft.pdf www.unece.org/fileadmin/DAM/trans/doc/2011/wp29/WP29-153-12e.pdf 26 RIVM Report 2010: Effect of electric cars on traffic noise and safety 27 Delta/ECTunes Report 2011: External Sound For Electric Vehicles 25
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mendations to manufacturers for a system to be installed in vehicles to provide vehicle operation information to pedestrians and vulnerable road users. This guideline is intended as interim guidance until the completion of on-going research activities and the development of globally harmonized device performance specifications25.
HOW MUCH LESS NOISE IS POSSIBLE BY OPTIMAL WARNING SOUNDS In reference it is calculated that a complete replacement of ICE vehicles with electric vehicles will reduce the noise levels in cities with 3-4 dB26. It is important that we optimize the warning sounds so we don’t waste this environmental benefit. If the signals are optimised for audibility, suitability and annoyance and are emitted from a good sound system fulfilling the requirements there are the following benefits compared to the ICE vehicles27: • Only sound radiation in the direction of driving • The sound level of the drive sound is decreasing above 20km/h unlike the motor sound from ICE vehicles. • No idle sound when speeder is not pressed
Sound levels of the warning sounds are limited to same audibility as ICE motor sounds instead of a specified A-weighted sound pressure level (meaning 5-10 dB lower levels) No sound components below 100 Hz.
These issues mean that the noise pollution with the specified warning sounds and a good sound system is considerably less than from the ICE vehicles.
The following types of sounds are relevant28: Start sound: A short (1-2 sec) omni-directional sound indicating that the car is preparing to drive. An “attention catcher”. It may be a separate sound or the idle sound with a level increase of 10-15 dB. Idle sound: A stationary sound with constant frequency/pulse rate indicating that the car may move any moment or is moving slowly. The idle sound is the same as the drive sound at its lowest frequency.
WARNING SOUND RECOMMENDATIONS Signal types
This section aims to provide guidelines for suitable warning sounds, i.e. signals with sufficient audibility, good localization and recognition of vehicles and their maneuvers with minimum sound pressure levels and annoyance for the surroundings. In order to be recognizable and useful the sound should give information similar to the information pedestrians receive from sounds emitted by vehicles with internal combustion engines. The audibility in background noise of the warning sounds should be similar to the sound from an internal combustion engine.
Drive sound: The same as the idle sound, but modulated with the speed. The sound pressure level shall vary with speed. The Frequency of characteristic components (frequency of any tones, pulse rate for impulsive components or prominent frequency bands for broad band sounds) shall vary with speed. Additional sound characteristics may be added (e.g. the mimicking the sound from tyres on ravel with increasing average pulse rate with random fluctuations). Reverse sound: A sound or a sound characteristic that is added to the driving sound indicating that the vehicle is driving backwards. The sound shall be easy to localise i.e. with broad band characteristics,
Delta/ECTunes Report 2011: External Sound For Electric Vehicles
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multi-tones, pulses etc. The single frequency beepers known from trucks and vans are not recommended. They are difficult to localize, often to loud and many find them annoying.
Sound system recommendations The External Sound Generation System (ESG) consists in the principle of a controller which gets the driving mode information from the car and which controls a sound generator accordingly. The output from the sound generator is fed to a system of amplifiers and loudspeakers with at least two channels (front and rear speakers). To be able to reproduce the warning sounds and their changes in amplitude and frequency with speed, the system presumably need to be based on loudspeakers. Piezo beepers, horns or buzzers will probably not be able to fulfil the recommendations.
designed to allow microcontrollers and devices to communicate with each other within a vehicle without a host computer. CAN is a message based protocol, designed specifically for automotive applications. Indications for speed, driving direction and turning (steering wheel or indicating lights), acceleration/load are available.
The sound controller and sound generator shall be able to change the signals and sound outputs. The system should be able to give A-weighted sound pressure levels up to 75 dB(A) with the selected warning sounds in all measuring positions.
Drive Mode Information
The frequency range of the system should be least 200-2000 Hz (-10 dB). The system should roll-of with at least 12 dB/octave below 100 Hz29.
Controllerâ€“area network (CAN or CAN-bus) is a vehicle bus standard
There should be at least one speaker at each end of the car, one pointing forward and one backward covering front/sides and back/sides. To obtain the best directional characteristics the loudspeakers should not be hidden in cavities inside the car body but should be able to radiate freely in the wanted directions.
The External Sound Generation System shall be able to receive driving mode information (speed, acceleration, forward/reverse, on/off etc.) from the vehicleâ€™s data bus system e.g. CANBus, LIN etc. or receive analogue signals from the vehicle.
Delta/ECTunes Report 2011: External Sound For Electric Vehicles
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// ECTunes’ experiences with the project and methods, by Thomas Gadegaard
ECTunes’ participation the Sound ‘n’ Safe project has been both interesting and usefull. It has given us an opportunity to test our products and sound design guidelines that were developed in cooperation with Delta SenseLab in the “External sounds for electric cars” project. The process with the development of sounds for this project has given very useful input to the further development of the ECTunes sound core and provided some very good examples of how total soundscapes can be developed. It is not a question whether the developed soundscapes in the project are good or bad. The importance of this project is the contribution to the debate on how we make the next generation of electric vehicles safer. Is the use of external sound the right way to increase the pedestrian safety and especially for the blind and partially sighted? If yes, how do we add external sound on the vehicles without adding to the already noisy urban environment? As the first of its kind with focus on electric busses and 2 wheeled vehicles the Sound ‘n’ Safe project is an important input to start focusing not only on the electric cars – but on the silent electric vehicles in general. If the conclusion will be that external sound is the best way
to make these silent vehicles safe in the traffic it is important that a coming legislation include requirement to the sound designs to make them easy recognizable, warning and at the same time not add to the already existing noisy environment. Compared to the earlier studies that ECTunes has executed in cooperation with Delta SenseLab it has been interesting to follow a panel of “untrained” listeners/respondents and especially the feedback from the group of blind and partially sighted. Even though this project only included lab tests it has given important input to how to test electric vehicle sounds towards an “unprepared” panel of respondents. A natural next step would be to make the same test in a realistic urban environment with real vehicles and compare the results. The interesting part is if it is possible to reach the same results in a lab test as in a “live” test because the lab test method is much easier, faster and less expensive – in relation to test future sound scrapes for electric vehicles in large scale. ECTunes will use the results and conclusions from the Sound ‘n’ Safe project in the further development of our products and new research within soundscapes for silent electric vehicles.
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// Experiences with the project (sound design part) and the userdriven method from my point of view, by Yann Coppier, Studio Ovale Great because I liked the different stages in it: discussion, creation of sounds, user tests, feedback, reworking the sounds, user test, feedback and finalization. That was exciting, tough and fast. Also, it brought me to try and find out what would work for other people instead of what I just thought would be nice. Interesting also to see how a new category of users (namely the visually impaired ones) could significantly change the results. I should add that the feedback and analysis from etrans were very complete and stimulating. Frustrating because the result was very foreseeable in many ways (people thinking of a futuristic bus sound just as a smoother bus sound). Doing a designdriven project after the userdriven one was very good then: it seems everybody will go for a soft turbine sound and/or a ringtone-like system, as soon as you ask people. I think it’s a mistake, and that it mostly relies on the poor knowledge the industry has of sound. This part of the work allowed me to show other alternatives, and felt like a relief in some ways. To me this is mostly the beginning of a bigger project, in which sound should be taken into account from scratch. So many developments are possible that I think it was a shame to use one existing system instead of starting earlier and develop a brand new one, based on synthesis and interaction (think of sounds indicating the nervosity of the driver for instance). I believe in research, systematic and organized, and would like to work more in this direction.
Also understanding that a car doesn’t have to make a car sound will change a lot of things in the future, and might lead to some real evolution in the sound design area. But to get to that we must first have a better understanding of the way people feel about sounds. A thorough analysis of te language used to describe sounds would be a good start. To sum it up, here is how I think about future possibilities: Make a research group which includes sound design from the beginning. That could be done in conjunction with a sound design school, where students could participate in the work as part of their studies. Focus on different possible interface designs and their interaction with the outside world at the same time or before thinking about the sounds. Discuss and test different possible methods to generate the different types of sounds: types of synthesis, sampling, bringing out what’s in, analysing the outside world to blend in by generating a complementary sound etc. Then mix designerdriven and userdriven methods, starting from the designer’s perspective to avoid the trap of space turbine sounds: first a creative approach, free of constraints to help finding out different systems. Second a rationalization of that approach through physical /law constraints (how the sound will be diffused and what is legally acceptable). Finally test the sounds systematically through userdriven methods.
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”For some men who value the acceleration sound of the car engine, there can be a loss of identity by driving in a quiet electric car Anne Flemmert Jensen, Consumer Behaviour Researcher
Description of the sounds and method used This is mainly for the designerdriven part of the assignment, the userdriven one being already well documented. Note that each sound is in reality a full system: the amount of sounds generated goes way beyond what is shown in the movies, as they were developed to work in real-time environments including interaction with the environment. In that way they all could somehow be implemented directly in a bus or motorcycle.
Choises Bus Recognizable
Themes: classic/mechanical, cultural/science fiction, natural/sustainable. Motorcycle
Creating a library: sound possibilities • Categories / themes & coherence • Recognizable / Abstract • Movement / No movement • If yes, regular / irregular movement • Regular movement can be pulse or rhythm • Movement can appear on the pitch, in the amplitude, in the frequential domain, in the time domain • The content can be tonal or atonal. Annoyance is the key here. • How to create agressive or soft engines link to the product. • Adding a green/sustainable touch.
Recognizable Experimental Unknown
Decisions • Use of synthesizers for constantly evolving sounds. • Additive synthesis: analysis/resynthesis/Phase vocoding/Granular synthesis/Convolution.
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All these methods allow us to use changes in the pitch without altering the tempo, and vice versa. They also allow for considerable possibilities in terms of sonic manipulations. Bus 1 – “Mechanical Abstraction”. Recognizable sound, mechanic. FM Synthesis, 4 operators. All kinds of strange movements will be shown here. From unearthly vibrations, to quite familiar engine-like features. The sound should change depending on a lot of factors, like you’d find in a sound installation. Those factors will be speed, acceleration, angle of bending towards the ground (for a motorcycle), nervosity of the driver and presence (or not) of other engines around. When the engine is idle the sound will be humming. Bus 2 – “Untamed Nature”. Partly recognizable, natural/organic. Granular synthesis, 8 sampled oscillators. The overall sound at regular speed will be pleasing. Speed will be shown by an increasing amount of elements / animals in the sound. Then acceleration will make the sounds explode more or less violently depending on how strong it is, like accelerated neutrinos with small particles of sound moving fast around itself. When the engine stops, the only sound is an insect at night. Bus 3 – “Animal evolution”. Unknown sound, natural/organic. Subtractive synthesis, 5 oscillators. Two arms sweeping the floor in the front front, like a beetle’s mouth. Kind of organic wheels on the side, independent but quite similar to each other. When the bus turns on the right, the right side goes faster and the left side goes slower. In the
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middle, a kind of centipede is running. When the bus stops the animal is breathing/resting. Motorbike 1 – “Perpetual movement illusion”. Recognizable sound, old school/mechanic. Additive synthesis, 10 oscillators. A constantly evolving sound, up (forward) or down (backwards). The speed is shown by the width of the pattern (more or less up and down), while acceleration is shown by its speed. When slowing down and ultimately stopping the sound will end up on an foggy note. Motorbike 2 – “Exploring space”. Partly recognizable sound, cultural/abstract. Spectral synthesis, 96 oscillators. A stable engine will make you hear a subtle ever-changing spectral loop (won’t include beats for the moment, to avoid annoyance). Any acceleration or slow down will disturb the loop, inducing changes in its structure and stability. When the engine starts or stops the sound will be very close to a DJ scratch. Then the idle sound is always the same, spatial pattern. A few stars pop in from time to time. Motorbike 3 – “Sea travellers”. Unknown sound, nature/organic. Convolution, 12 soundscapes. The way the engine is driven will make it sound like different types of seas. Waves will come when the driver breaks for instance, and if he’s driving agressively and fast he’ll create a storm. The idle sound will be of gentle waves arriving ashore. The technique used will still make the sounds hardly recognizable, apart from the liquid feel. Most of the movement within the sound will come from the acceleration/slow down. Regular speed will leave you in one type of sea, from calm to angry.
The Danish Environmental Protection Agency has calculated that between 200-500 people die annually of illnesses resulting from traffic noise. There are equally as many who die in traffic accidents.
Silent cars are highly dangerous for the blind! Birgitte Rasmussen, Danish Association for the Blind
It is about safety for soft road users, but also about branding!
Can noise pollution be replaced by a pleasant experience?