Unlike most FM synthesis chips that require every instrument to be programmed from scratch, the YM2413 features a built-in Instruments ROM containing 15 hard-coded melody patches and 5 rhythm sounds.
instruments.bin for YM2413 is typically 48 bytes; the first 8 bytes define the single user-programmable FM instrument (op1+op2 parameters), the remaining 40 bytes are often unused or hold multiple patches. The file can be loaded directly via emulators or sound driver code to replace the default instrument 16 (user slot). ym2413+instrumentsbin
If you need a specific instruments.bin example or help converting patches from other FM chips (like OPL2/OPL3), let me know! Unlike most FM synthesis chips that require every