Change Ringing
We have also begun to study those permutations that correspond to the notes produced during change ringing of bells. Over simplifying the definition, we begin with a downward scale and then for each successive permutation exchange some pairs of adjacent notes. The result is a fairly complex melody with a recognizable structure to it. We perturb this structure by gradually sharpening or flattening certain notes in the base set.
One student who joined the project in summer 1999 has a degree in psychology. We hope to use him to design and perform experiments to determine whether computer users can distinguish among melodies generated by different comma-free codes over the same alphabet.
This will be a change from our current work of conveying information by choice of notes. In theory, we could use comma-free codes to represent 20 different values using only 4 notes.