The SFZ Format
The SFZ format is an open source, non-proprietary file format used to create virtual instrument sample libraries, in the same vein as Native Instrument's NKI format for Kontakt. In order to open and use an SFZ file, an SFZ compatible player is required. A number of these exisit, but the most popular option is Plogue's sforzando, which is free to download for both Mac and Windows and acts as either a standalone application or a VST/AU/RTAS/AAX plugin. When combined with sforzando, the SFZ format offers many of the same features as Kontakt instruments, including multiple velocity layers, key switches, and round robin.
Please note that my SFZ virtual instruments are built around and tested in sforzando, so they might not work as intended when loaded into any other application, although any that are labled as being SFZ level 2.0 or 1.0 (not 2.0+) should work in other SFZ compatable players.
If you have any questions or run into any issues, while using my virtual instruments, feel free to Contact Me!