This field called Preface. Here you will be able to add any text or media using all styling options from content editor.
This field is created to show any text that users need to have before showing the audio. Preface field is optional so you can easily remove this field.
This text added in "Description" area. Here is a simple example of how Audio post created with Zombify frontend uploader in Boombox Viral theme.
This post can have: Title, Excerpt, Preface, Source URL, Credit, Description, Featured image, Categories and tags. Every user can easily have audio post without "Excerpt", "Preface", Credit", "Source URL", Description, Category, Tags. In this post we have added Embed URL from SoundCloud, however, there is an option to add Mixcloud Embed URL and upload an Audio file in MP3 format.