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| Beeps and why they are usually bad ("Ecosystem of beeps" blog entry). Tone types. Audio readback best practices. Look at med reminder for some of these. Voice input. Vibrate is just crappy haptics. Include it. | [[http://www.amazon.com/gp/product/1449394639/ref=as_li_tf_tl?ie=UTF8&tag=4ourthmobile-20&linkCode=as2&camp=217145&creative=399373&creativeASIN=1449394639|{{attachment:wiki-banner-book.png|Click here to buy from Amazon.|align="right"}}]] == The Big Tooter == High atop Mount Oread, in the picturesque city of Lawrence, Kansas, stands a whistle—a whistle with quite a history composed of tradition, controversy, and headache that started about a hundred years ago. The whistle is known as the “Big Tooter.” March 25, 1912, 9:50 a.m.: a deafening shrill begins. For five earsplitting seconds the power plant steam whistle at the University of Kansas sounds. The sound is so loud it can be heard from one side of the city to the other. It’s the first time the whistle is used to signal the end of each hour of class time. According to the student newspaper The Daily Kansan, the whistle was not only used to replace the untimely and inconsistent ringing of bells with a standard schedule of marked time, but was also used to remind professors to end their lectures immediately. Prior to the whistle, too often professors would keep students past the 55 minutes of class time, causing them to be late for their next class. With the new sound system in place, even the chancellor had something to say. “If the instructor isn’t through when the whistle blows,” said KU Chancellor Frank Strong to the student body, “get up and go.” == The Big Tooter Today == For the past 100 years, the Big Tooter has been the deafening reminder to faculty and students about punctuality and when to cover their ears. I can say I, too, was one of those students who would purposely alter my walk to class to avoid that sound at its loudest range. But despite the fact that the steam whistle was excruciatingly loud, it served its purpose as an audio alert. It was so unique that it was never misunderstood, and is so reliable that it is always trusted. == The Importance of Audition == From the preceding example we see that people can benefit from specific sounds that are associated with contextual meaning. Using audition in the mobile space can take advan- tage of this very important concept, for the following reasons: * Our mobile devices may be placed and used anywhere. In these constantly chang- ing environmental contexts, users are surrounded by external stimuli which are constantly fighting for their attention. * The device may be out of our field of view or range of vision, but not our auditory sensitivity levels. * Using audition together with other sensory cues can help to reinforce and strengthen users’ understanding of the interactive context. * The user may have impaired vision—either due to a physiological deficit or from transient environmental or behavioral conditions—thus requiring additional auditory feedback to assist him in his needs. * The user may require auditory cues to refocus his attention on something needing immediate action. [[http://www.flickr.com/photos/shoobe01/6501542443/|{{attachment:AudioIntro-Volume.png|Figure 12-1. Control of volume level is usually still performed by hardware keys due to its importance. This makes it an interesting control as it is always pseudomodal. The user enters the mode by using the keys, which loads a screen, layer, or other widget to indicate the volume change. Related controls, silence and vibrate, are associated with this mode as well.}}]] == Auditory Classifications == Audible sounds and notifications have become so commonplace today that we have learned to understand their meaning and quickly decide whether we need to attend to them in a particular context. === Warnings === === Alerts and Notifications === === Error Tones === === Voice Notifications === === Feedback Tones === == Audio Guidelines in the Mobile Space == [[http://www.flickr.com/photos/shoobe01/6501544267/|{{attachment:AudioIntro-Speech.png|Figure 12-2. Voice inputs can help users in situations where visibility is limited or nonexistent, but they have to be part of a complete voice UI. Don’t just perform one or two steps of a process and then require the user to read and provide feedback on the screen.}}]] === Signal-to-Noise Ratio Guidelines === People will use their mobile devices in any environment and context. In many situations, they will rely on the device’s voice input and output functions during use. See Figure 12-2. But, whether the person is inside or outside, her ability to hear certain speech decibels apart from other external noises can be quite challenging. Here are some guidelines to follow when designing mobile devices that rely on speech output and input: * Signal-to-noise ratio (S/N) is calculated by subtracting the noise decibels from the speech decibels. * To successfully communicate voice messages in background noise, the speech level should exceed the noise level by at least 6 decibels (dB) (Bailey 1996). * A user’s audio recall is enhanced when grammatical pauses are inserted in synthetic speech (Nooteboom 1983). * Synthetic speech is less intelligible in the presence of background noise at a 10 dB S/N. * When the noise level is +12 dB to the signal level, the consonants m, n, d, g, b, v, and z are confused with one another. * When the noise level is +18 dB to the signal level, all consonants are confused with one another (Kryter 1972). === Speech Recognition Guidelines === In addition to the signal-to-noise guidelines in the preceding section, you must under- stand how users recognize speech. The following guidelines will assist you when designing [[Voice Notifications]]: * Words in context are recognized more when they are used in a sentence than when they are isolated, especially in environments with background noise. * Word recognition increases when the words are common and familiar to the user. * Word recognition increases if the user is given prior knowledge of the sentence topic. == Audio Accessibility in the Mobile Space == When designing for mobile, as with any device always consider your users, their needs, and their abilities. Many people who use mobile devices experience visual impairments. We need to create an enriching experience for them as well. Recently companies have been addressing accessibility needs as standard functions in mobile devices. Before this, visually impaired users were forced to purchase supplemental screen reader software that worked on only a few compatible devices and browsers. These are quite expensive, starting at around $200 to $500. === Accessibility Resources === Here are useful resources on audio accessibility. Included is information on types of as- sistance technologies companies are using in mobile devices today. * Apple has integrated VoiceOver, a screen access technology, into its iPhone, iPod, and iPad devices. For more information on Apple’s accessibility commitment, visit http://www.apple.com/accessibility. * Companies such as Code Factory have created Mobile Speak, a screen reader for multi-OS devices. See Code Factory’s site at http://www.codefactory.es/en. * For additional information on accessibility and technology assistance for the visually impaired, we recommend viewing the American Foundation for the Blind’s website, http://www.afb.org. * We also recommend the following websites geared toward accessibility of mobile devices for all: * http://www.accesswireless.org/Home.aspx * http://www.mobileaccessibility.info/ * http://www.nokiaaccessibility.com/ == The Importance of Vibration == === Common Haptic Outputs on Mobile Devices === === Haptic Concerns === == Patterns for Audio & Vibration == ------- = Discuss & Add = Please do not change content above this line, as it's a perfect match with the printed book. Everything else you want to add goes down here. == Examples == If you want to add examples (and we occasionally do also) add them here. == Make a new section == Just like this. If, for example, you want to argue about the differences between, say, Tidwell's Vertical Stack, and our general concept of the List, then add a section to discuss. If we're successful, we'll get to make a new edition and will take all these discussions into account. |
The Big Tooter
High atop Mount Oread, in the picturesque city of Lawrence, Kansas, stands a whistle—a whistle with quite a history composed of tradition, controversy, and headache that started about a hundred years ago. The whistle is known as the “Big Tooter.”
March 25, 1912, 9:50 a.m.: a deafening shrill begins. For five earsplitting seconds the power plant steam whistle at the University of Kansas sounds. The sound is so loud it can be heard from one side of the city to the other. It’s the first time the whistle is used to signal the end of each hour of class time.
According to the student newspaper The Daily Kansan, the whistle was not only used to replace the untimely and inconsistent ringing of bells with a standard schedule of marked time, but was also used to remind professors to end their lectures immediately. Prior to the whistle, too often professors would keep students past the 55 minutes of class time, causing them to be late for their next class. With the new sound system in place, even the chancellor had something to say.
“If the instructor isn’t through when the whistle blows,” said KU Chancellor Frank Strong to the student body, “get up and go.”
The Big Tooter Today
For the past 100 years, the Big Tooter has been the deafening reminder to faculty and students about punctuality and when to cover their ears. I can say I, too, was one of those students who would purposely alter my walk to class to avoid that sound at its loudest range. But despite the fact that the steam whistle was excruciatingly loud, it served its purpose as an audio alert. It was so unique that it was never misunderstood, and is so reliable that it is always trusted.
The Importance of Audition
From the preceding example we see that people can benefit from specific sounds that are associated with contextual meaning. Using audition in the mobile space can take advan- tage of this very important concept, for the following reasons:
- Our mobile devices may be placed and used anywhere. In these constantly chang- ing environmental contexts, users are surrounded by external stimuli which are constantly fighting for their attention.
- The device may be out of our field of view or range of vision, but not our auditory sensitivity levels.
- Using audition together with other sensory cues can help to reinforce and strengthen users’ understanding of the interactive context.
- The user may have impaired vision—either due to a physiological deficit or from transient environmental or behavioral conditions—thus requiring additional auditory feedback to assist him in his needs.
- The user may require auditory cues to refocus his attention on something needing immediate action.
Auditory Classifications
Audible sounds and notifications have become so commonplace today that we have learned to understand their meaning and quickly decide whether we need to attend to them in a particular context.
Warnings
Alerts and Notifications
Error Tones
Voice Notifications
Feedback Tones
Audio Guidelines in the Mobile Space
Signal-to-Noise Ratio Guidelines
People will use their mobile devices in any environment and context. In many situations, they will rely on the device’s voice input and output functions during use. See Figure 12-2. But, whether the person is inside or outside, her ability to hear certain speech decibels apart from other external noises can be quite challenging. Here are some guidelines to follow when designing mobile devices that rely on speech output and input:
- Signal-to-noise ratio (S/N) is calculated by subtracting the noise decibels from the speech decibels.
- To successfully communicate voice messages in background noise, the speech level should exceed the noise level by at least 6 decibels (dB) (Bailey 1996).
- A user’s audio recall is enhanced when grammatical pauses are inserted in synthetic speech (Nooteboom 1983).
- Synthetic speech is less intelligible in the presence of background noise at a 10 dB S/N.
- When the noise level is +12 dB to the signal level, the consonants m, n, d, g, b, v, and z are confused with one another.
- When the noise level is +18 dB to the signal level, all consonants are confused with one another (Kryter 1972).
Speech Recognition Guidelines
In addition to the signal-to-noise guidelines in the preceding section, you must under- stand how users recognize speech. The following guidelines will assist you when designing Voice Notifications:
- Words in context are recognized more when they are used in a sentence than when they are isolated, especially in environments with background noise.
- Word recognition increases when the words are common and familiar to the user.
- Word recognition increases if the user is given prior knowledge of the sentence topic.
Audio Accessibility in the Mobile Space
When designing for mobile, as with any device always consider your users, their needs, and their abilities. Many people who use mobile devices experience visual impairments. We need to create an enriching experience for them as well.
Recently companies have been addressing accessibility needs as standard functions in mobile devices. Before this, visually impaired users were forced to purchase supplemental screen reader software that worked on only a few compatible devices and browsers. These are quite expensive, starting at around $200 to $500.
Accessibility Resources
Here are useful resources on audio accessibility. Included is information on types of as- sistance technologies companies are using in mobile devices today.
Apple has integrated VoiceOver, a screen access technology, into its iPhone, iPod, and iPad devices. For more information on Apple’s accessibility commitment, visit http://www.apple.com/accessibility.
Companies such as Code Factory have created Mobile Speak, a screen reader for multi-OS devices. See Code Factory’s site at http://www.codefactory.es/en.
For additional information on accessibility and technology assistance for the visually impaired, we recommend viewing the American Foundation for the Blind’s website, http://www.afb.org.
- We also recommend the following websites geared toward accessibility of mobile devices for all:
The Importance of Vibration
Common Haptic Outputs on Mobile Devices
Haptic Concerns
Patterns for Audio & Vibration
Discuss & Add
Please do not change content above this line, as it's a perfect match with the printed book. Everything else you want to add goes down here.
Examples
If you want to add examples (and we occasionally do also) add them here.
Make a new section
Just like this. If, for example, you want to argue about the differences between, say, Tidwell's Vertical Stack, and our general concept of the List, then add a section to discuss. If we're successful, we'll get to make a new edition and will take all these discussions into account.