This post concludes a series of blog posts that I wrote about a presentation that I gave introducing museum people to the concept of sonification, representing data with nonspeech audio.
Earlier posts in the series are
Introducing Sonification, in which I discussed using sound to enhance storytelling.
Exploring Scientific Concepts And Data With Sonification in which I showed that sonification is an effective tool for learning scientific concepts and analyzing data giving examples from the field of astronomy.
In this post, I share design considerations for creating sonification—choices that exhibit designers can make when exploring a concept with audio.
Design choices for sonification used to communicate information should be considered carefully because they affect the listener’s understanding of the data being sonified. Data can be mapped to sonic dimensions, such as volume, pitch, tempo, timbre and location in the stereo field. A sound designer may choose acoustic or synthesized sounds, and create a sonification in a variety of musical styles.
Choosing a major or a minor key alters the mood of the musical piece influencing the way the listener interprets the data being sonified. One research group created a sonification of changes in the frequency of tree species in the Alaskan forest through time. They used a d minor scale to represent the falling numbers of yellow cedar trees in the Alaskan forest. The key of d minor expresses sadness about climate change.
An alternative musical choice that they did not make would have been to represent the rising number of western hemlock trees in a major key evoking a mood of happiness. However this would have been an ineffective message because the western hemlock is adapted to warmer temperatures and is moving northward due to global warming, the same phenomenon that is causing yellow cedar numbers to decline.
For more details, read Using Data Sonification to Overcome Science Literacy, Numeracy, and Visualization Barriers in Science Communication This paper was published in Frontiers in Communication.
Sound designers can compose sonification using audio editing software like Pro Tools, Logic Pro, or Garage Band. Ambient sounds that are specific to the project can be added to these compositions.
Public domain audio files are available in online databases.
Researchers need to analyze large datasets, and they may not have the time to create the custom-made sonifications that are effective for public outreach. Automated tools are suitable for sonifying large datasets and for running the many queries necessary for data analysis. Examples of automated tools include:
The SAS Graphics Accelerator adds features to data visualizations including text descriptions, tabular data, and interactive sonification.
IMAGE is a browser extension that will send a selected graphic to the IMAGE server. The graphic is rendered as a sonification with spatial audio.
Highcharts Sonification Studio is a partnership between Highcharts and the Sonification Lab at the Georgia Institute of Technology.
Sonification can be combined with text-based audio description just as visual graphs have text-based labels. Sonification gives the listener first-hand knowledge of the data trends.
The research project called Accessible Oceans combines description and sonification. Listen to the Ocean Outgassing Sonification.
Explaining concepts in an auditory way is a learned skill that many people who are sighted do not have the opportunity to develop. The examples of sonification described in this post are engaging, and I hope that they will encourage exhibit designers to include sonification in exhibits that rely on visual displays of data. This would provide multisensory opportunities for everyone, and it would increase access for people who are blind.