Sonified Line Graph

Context:

You are designing an audio-only display to present one or more two-dimensional (function-based) data sets.

Problem:

You need to convey the quantitative information as accurately as possible.

Forces:

• The dimensional value of the data needs to be perceived, relative to measurement scale.
• Multiple data sets must be properly perceived relative to one another.

Solution:

Use the metaphor of a two-dimensional line graph. Map the X-axis of the graph to time, and map the y-axis of graph to the pitch, timbre and/or volume of musical notes.

Additionally: Use musical sounds rather than pure sine waves; Only use notes within a useful perceptible range (e.g. MIDI #35-100); Present graphs at a speed that does not impair comprehensibility (e.g. 50-70ms between values); Use stereo-panning to separate data series; Present data series in Parallel Mode rather than Serial Mode.

Rationale:

There have been a number of experiments showing that sonified line graphs are an efficient way of displaying two-dimensional data (A recent instance is from Bonebright [see examples below]). Brown et. al. provides some comprehensive justification for most of the above dot points [see examples below].

For Example:

• Brown, L. and Brewster, S. “Drawing By Ear: Interpreting Sonified Line Graphs”, in Proceedings of the International Conference on Auditory Display ICAD 2003, Boston, July 6-9, 2003.
  • [Paper: http://www.icad.org/websiteV2.0/Conferences/ICAD2003/paper/37%20Brown1-%20drawing.pdf]

• Walker, B. and Cothran, J. “Sonification Sandbox: A Graphical Toolkit For Auditory Graphs”, in Proceedings of the International Conference on Auditory Display ICAD 2003, Boston, July 6-9, 2003.
  • [Paper: http://www.icad.org/websiteV2.0/Conferences/ICAD2003/paper/39%20Walker1-%20sandbox.pdf]

• Brown, L., Brewster, S., Ramloll, R., Burton, M. and Riedel, B. “Design Guidelines For Audio Presentation Of Graphs And Tables”, in Proceedings of the International Conference on Auditory Display ICAD 2003, Boston, July 6-9, 2003.
  • [Paper: http://www.icad.org/websiteV2.0/Conferences/ICAD2003/paper/69%20Brown2-%20guidelines.pdf]

• Bonebright, T., Nees, M., Connerley, T. and McCain?, G. “Testing The Effectiveness of Sonified Graphs for Education: A Programmatic Research Project”, in Proceedings of the International Conference on Auditory Display ICAD 2001, Espoo, Finland, July 29 – Audust 1, 2001.
  • [Paper: http://www.acoustics.hut.fi/icad2001/proceedings/papers/bonebri1.pdf]