This paper reports initial results from a study which investigated whether different media combinations could be shown to improve students' understanding of computer-based learning materials and to determine whether student learning style affected student understanding for different media combinations. Three groups of participants were given a presentation, each using different media combinations to present a topic. Dual coding theory was used as the basis for designing the presentation. Results indicate that participants' understanding was enhanced when the computer-based learning materials were presented using sound and diagrams. Understanding was worse when materials were presented using text and diagrams. The result supports the predictions of dual coding theory. Furthermore, the results indicate that the sound and diagram combination can improve participants' understanding regardless of their preferred learning style, and that intuitive learners seem to be exceptionally volatile to different media combinations. (Contains 11 references.) (Author)