A simg file extension is related to the Synclavier disk image format.
SIMG file extension - Synclavier disk image
What is simg file? How to open simg files?
File type specification:
The simg file extension is related to the Synclavier for Mac, an audio software for Apple Mac computers.
The simg file contains disk image created with Synclavier.
Most likely obsolete file format.
This simg file type entry was marked as obsolete and no longer supported file format.
This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.