OMA (Sony OpenMG audio)
The OMA Audio file format
The OMA file extension was developed by Sony and it is known as a Sony OpenMG music file. This type of file is a music file and it is proprietary to Sony. OMA files are saved in the Sony ATRAC format. ATRAC stands for Adaptive Transform Acoustic Coding. The OMA file sometimes includes DRM copy protection within the file. This is done to stop people from playing music files that are specific to Sony devices from being played on devices or computers that are unauthorized. Because of this type of protection, it is a common file type that causes problems for people. You may have to convert this to a different file type to use it.
Technical details of OMA files
The OMA file type was primarily used to distribute music for Sony. They used the Sony CONNECT Music Store to handle this function. However, this service was discontinued in early 2008 and the file extension is currently not used for any other file. If you still have music in the OMA file format, you may be able to play it on other Sony devices. However, this will not work for all devices. If you don’t have the original device you used to create or listen to the OMA files, it will need to be converted to a different type of file before it becomes useable.