Soundfont SF2 files are a type of soundfont format used in digital musical instruments and software synthesizers. They contain samples and other data necessary for generating musical sounds. The SF2 format, in particular, became a standard for soundfonts due to its efficiency in storing and playback of high-quality sounds. For the Ensoniq TS-10, the use of SF2 soundfonts meant that musicians and composers could significantly expand the instrument's built-in sounds with custom or additional sounds, ranging from realistic instrument emulations to more experimental and ambient textures.