According to copyright law, permission must be obtained from the copyright owners in order to use a piece of music in any production. Since there are 2 copyrights involved any musical recording - the recording itself and the underlying composition - permission must be obtained from both rights holders. A Master License is permission from the owner of the recording ( usually the record label or songwriter ). A Synchronization License is permission from the Publisher if there is one or the Songwriter ). You need both of these licenses to legally use music in a media project. These license can be a combo. license : a "Master/ Sync. License" especially if the songwriter retains the ownership of the recording and publishing. In any case, using music without permission is “copyright infringement,” a serious legal infraction. Whether you’re using one second of a song or the entire song, a valid Master/Sync license is still required.
So, you have 3 main options.
1) To license commercial music ( like say you want to use A Black Keys song in your movie ) you can hire a music supervisor to clear the rights and negotiate a license deal with their record label and publishers so you can use the music in your project.
2) You can hire a composer to create custom music your project. This requires a Composer Agreement which is different than a Master / Sync License. in addition, many scored films use both licensed music and custom score.
Both of these options are time consuming and costly options and, while can be worth the extra effort, are well suited for larger budgeted feature films, TV series , major brand commercials, and video games.
3) The third option is to license music from a music library. Music libraries provide a fast, simple and affordable solution for the vast majority of video, commercials, indie films and media projects. Music libraries and catalogues provide a simple, convenient and affordable source for music for any production. The music is designed to be “pre-cleared” , both permissions are already given, so that licensing is fast and convenient. Most libraries maintain standardized “rate cards” so that the prices are pre-determined for various media projects ( YouTube videos or webcasts have a different licensing rate than that of an indie film showing at a festival and a TV Commercial licensing rate is different from those…and so on ) Finally, tracks in music libraries are generally created with certain applications in mind (like corporate videos, commercials, trailers, underscore, etc.) , created to be easily edited into the film and are categorized using metadata in such a way that makes it easy to find exactly the right mood and track for your production. Smaller "Boutique" libraries usually offer more indie, creative and fresh options, than larger "production music libraries".
Small, composer run boutique music catalogues like Magnetic West Music's DIY Licensing Store play an indispensable role in today’s production world by offering a fast, convenient and affordable way to instantly access music that has a unique artistic edge over the larger production music libraries.