Due to the COVID19 crisis, this event has unfortunately been canceled.
From this distinguished event website:
After rapidly presenting how symmetries play an interesting role in nature, art, and science, François Bergeron and Jurgen Petrenko of the Kitchener-Waterloo Symphony will explain and illustrate how Bach uses mathematical symmetries in writing the scores for his music. This will partly be done via an interplay between a pictoral description of the symmetries of the scores, and a live rendition on the harpsichord of the result for the audience.
More information on this page.