Earlier BIOS revisions (such as SCPH-1002) were notorious in the emulation community for having audio glitches or compatibility issues with specific titles. The "550x" series was the standard for "universal" compatibility for a long time.
: A common point of confusion in the emulation scene involves MD5 checksums. Some emulator cores, particularly older versions of Mednafen PSX, have been noted to look for a specific MD5 hash that actually belongs to the scph5552.bin file while labeling it as scph5502.bin . playstation scph5502 v30 europe bios scph5502bin
Respect the hardware, dump your own BIOS legally, and when you hear that 50Hz boot-up chime, know that you are hearing history—coded in binary, locked in a chip, a world where PAL ruled. Earlier BIOS revisions (such as SCPH-1002) were notorious