The file is typically exactly 8 bytes per instrument, arranged sequentially.
Each 8-byte patch corresponds to one YM2413 user instrument (slot 16 in most implementations). ym2413+instrumentsbin
If you are analyzing VGM (Video Game Music) files from the Sega Master System, the custom instrument data is embedded inside the .vgm or .gz file itself. You don't need an external instruments.bin. The player writes the instrument definition to the chip every time the instrument changes. The file is typically exactly 8 bytes per
The YM2413 (OPLL) is a 4-operator FM synthesis chip by Yamaha.
Key features: The famous instruments
The famous instruments.bin is a small binary file (often 48 bytes) that writes custom FM parameters into the user instrument slot (channel 8 or channel 0 depending on implementation).