Audio on The Internet

Sound in The Human-Computer Interface

A number of studies have shown how audio contributes to the human-computer interaction process to provide a richer, more robust environment than with mere graphic feedback. Auditory feedback can present further information when the bandwidth of graphic information has been exhausted, as is often the case with the present emphasis on graphic presentation. By expanding conventional interfaces in another dimension, sounds make tasks easier and more productive. Other studies have even shown certain types of information to be represented better by sound than through graphics or text. Additionally, audio feedback may complement graphics and text to create valuable redundancy, reinforcing or reconfirming a concept in the user's mind.

For example, it seems reasonable to assume that the sounds used to represent a particular event will be a factor in whether that event is effective or not. As pointed out above, one criteria for selection of sounds could be consistency with the physical world. We could start by making the sound of an on-screen button consistent its function.

As each type of switch in real-life has its own texture and resistance, each type of software switch (e.g. an on-screen button) could have its own sound which the user would associate with that button and that function. As familiarity with the sound grows, the user will associate a sound not only with its respective button, but also with its function. So not only will the user know by the auditory cue their action was registered, they will also know, with utter immediacy, what action was performed - without having to read a label or other description within a dialog box. Graphics and text could then be used to provide other information, thereby widening the effective bandwidth of conveyed information.

Many systems use robust audio feedback with great success. The telephone is a very general example that uses audio feedback exclusively. Perhaps the most intense interactive systems in general use are for playing video games. Fast-action video games use audio feedback extensively to aid in rapid interaction. It has been shown that performance in such applications drops when the audio feedback is removed. Perhaps a user could wield a business or scientific application with greater speed and ease of use with audio feedback. In doing so, the productive process might become more enjoyable as well.

Audio also promises to bridge the gap between sight-impaired users and graphic user interfaces (GUIs). It is ironic that the desktop/windows systems on personal computers have enable so many persons to become computer literate and yet have abandoned the blind, who in the past have been productive using text-based interfaces and refreshable Braille modules. Various groups, the Mercator Project at the Georgia Institute of Technology and the GUIB project funded by the European Community, are working on audible complements for the desktop metaphor. Emphasis has been placed on determining the best sound to correspond with each action, finding sounds which work effectively in combination, and developing a system of localization so that sounds are correctly associated with their respective graphic object. Yet, as Braille is not a literal physical representation of characters, perhaps a metaphor for the blind should not be a literal representation either. Menus and windows are not objects which the blind relate to, so why try to make their use audible? The blind do have a rich auditory experience that could provide for a unique metaphorical environment.

Considering the popularity of the World Wide Web, some of the most important work having to do with auditory displays with respect to the Internet is Albers' and Bergman's "The Audible Web: Auditory Enhancements for Mosaic". Multimedia and hypertext systems provide more information at a faster pace, requiring more user participation to control the information flow. Because an abundance of information arrives in the visual mode, feedback in the form of audio might ease this process:

We chose Mosaic as a test platform for auditory enhancements because it exhibits known HCI problems: users get little or no feedback about the size and content of information referenced by links, time to obtain that information, and the results of ongoing processes. The highly visual task of scanning through text for links suggested to us that Mosaic users could benefit from audio. By using audio rather than visual enhancements, our aim was to provide more information while shifting additional cognitive load to a different modality.
As a result of modifying Mosaic, the researchers found that audio feedback helpfully and unobtrusively complemented the primarily visual task of navigating the World Wide Web. They expect further research to reveal which types of audio cues are better suited for each event and deemed acceptable by the user.

Foreseeable difficulties in using sound as an interface

Audio on The Internet