Currently, an international application must contain a graphic reproduction of your mark. From February 1, graphic reproductions will no longer be required, providing holders who wish to seek protection of non-traditional marks through the Madrid System with more flexibility.
You can file an international application for a sound mark, motion mark or other types of multi-media marks represented in digital format so long as the representation of your basic mark is in the same format.
For more information see WIPO website.