We would like to develop an exciting variety of experiences involving sounds, from simple sine waves to synthesized speech, to share with our students the breadth of the aural world. A list of possible demonstrations and exercises is included below. In order to do this, we must start by creating core tools for manipulating complex sounds in interactive, web-based learning experiences, complete with informative documentation and interesting variables to manipulate.
Davidson College is providing limited summer support to Boye and Munger to begin work developing these tools (Summer 2000) as well as access to a variety of sound and computer hardware and software already owned by the Davidson Physics and Psychology departments. In addition, the College previously funded Boye as part of a larger grant to the Physics Department (Summer 1998).
After teaching courses on the physics of sound and the psychology of sound, we find there is a great deal of overlap in terms of the kind and nature of demonstrations and active learning examples that we would like to provide to engage our students interactively. An exciting new possibility for these demonstrations involves the use of sound technology afforded by computers. Currently, this material is limited to demonstrations on recorded media. The static nature of recorded media provides little opportunity for exploration and experimentation for the individual student. Existing demonstrations are not appropriate for our students, being overly simplified, in scattered locations, and housed at generally ill-maintained web sites with little useful documentation.
During the summer of 1998, Boye developed several java-scripted sound demonstrations that used existing physlets (http://webphysics.davidson.edu/dmb/default.html). These original physlets developed at Davidson provided only monaural output up to 3500 Hertz, which is inadequate for the full range of phenomena we are interested in including in our courses. Stereo output with frequencies up to 16,000 Hertz would allow us to fully explore sound phenomena. In order to develop web-based exercises that include more complex sounds, like chords and orchestral timbre, we need to understand what sound manipulations are possible in the web environment, and which of these are potentially useful for our teaching concerns. This will clearly involve extensive programming in java, a programming language both of us will need to learn, and some additional reading in acoustical psychophysics and the perception of voice and music to enable careful selection from the range of phenomena with which we are already familiar.
The kind of interactive exercises and demonstrations that we are envisioning are simply not available, in part because of the interdisciplinary nature of the project. With the development of a set of complex sound manipulation tools, we will be able to engage our students actively in the exploration of how it is that we hear things-using sounds that are not limited to simple tones or monaural presentation. These sound manipulation tools would be of use in a wide range of physics and psychology courses that touch on the sound or sound perception (Phys 115: Musical Technology, Phys 120: General Physics, Phys 130: General Physics with Calculus, Phys 330: Intermediate Mechanics, and Psy 101: General Psychology, Psy 276: Cognitive Psychology, and Psy 301: Research Methods - Sensation & Perception). In addition, such a set would also expand the range of possible senior thesis projects in psychology, allowing interested senior students to develop research-quality sound stimuli similar to the visual stimuli that Munger uses in her research.
The purpose of developing interactive exercises is to improve the student's understanding of the critical content by allowing students to develop more elaborative encoding of the material. Individuals who work with and manipulate information, or elaborately encode it, perform better on subsequent tests (Bradshaw & Anderson, 1982). Learning about phenomena that are fundamentally dynamic, like sound and perception which change with time, is difficult when the presentation is static, and elaborative encoding is necessarily abstract. For example, understanding how variables alter circumstance over time is difficult to convey with static presentation. However, it is not enough to believe that a new technology will work, you must be prepared to test whether or not students are learning the material better with the new method. Boye and Munger already have measurements of how well students learn the various acoustic information without access to interactive exercises because they have each been teaching these courses for a number of years at Davidson College. The same type of tests and assignments (ranging from in-class essay exams to lab reports) will be administered to students who have been required to use the interactive exercises as part of the their course work. When appropriate, the same questions will be asked for direct item comparisons between classes. If dynamic presentation and on-line manipulation of the material improve understanding by allowing for more elaborative encoding, the quality of the student work should improve, both on in-class exams and written work.
The question of how to effectively use the interactive nature of the web is being asked by more and more faculty, from a variety of disciplines. Our experience of developing interdisciplinary demonstrations would allow us to provide useful guidelines and ideas for how to decide what to try interactively. In addition, we would be happy to make the java procedures themselves available to interested faculty, with the departments of music and the foreign languages most likely to find it useful to manipulate sound. We would pursue publication of these demos in the appropriate teaching journals in both physics and psychology.
Bradshaw, G. L. & Anderson, J. R. (1982) Elaborative encoding as an explanation of levels of processing. Journal of Verbal Learning and Verbal Behavior, 21, 165-174.