SoundFont 1.0
From Just Solve the File Format Problem
SoundFont 1.0 (also known as Emu Sound Font) is a format used to store instrument patches for MIDI synthesizers. The SoundFont 1.0 format is based on RIFF; the RIFF type identifier is "sfbk".
See also SoundFont 2.0.
Identification
Files begin with ASCII "RIFF", and have "sfbk" at offset 8.
In most cases, this is followed by "LIST" at offset 12, "INFOifil" at offset 20, and bytes 01 00 at offset 32. The last 01 byte distinguishes major version 1 from major version 2.