This article explains what an SD2F file is, how to open it, and how to convert it to another file format.
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A file with the SD2F file extension is an audio file in the Sound Designer II format. The format was created by Digidesign, now called Avid, and is used with their Pro Tools software.
SD2F files contain audio data and other information relevant to the Pro Tools application. It is also used to exchange information between digital audio workstation (DAW) programs.
Corel's Roxio Toast software can archive an audio CD as a Roxio Jam Disc Image file, using the same Sound Designer II format. This type of SD2F file is a complete backup copy of the disc.