Apart from the reasons mentioned previously, your Prezi will really benefit from having sound if you decide to embed it into a website or share it on the Prezi explore page (http://prezi.com/explore/). There's more detail on this in Chapter 9, Prezi for Online Delivery, but making Prezi files that people can explore on their own is a huge benefit to people who might not have had the time to be at your live presentation. Adding sound into these online Prezis will help the users exploring them to understand the content quicker and more clearly.

You might decide to have audio recorded from your live session and have it played at certain points in your Prezi. Or you might just want to create some kind of mood for the user that fits with your Prezi's message. For the latter, you can use a music track that loops continuously when your Prezi is viewed online.

Some other benefits that using sounds can bring are: