The .chd (Compressed Hunks of Data) extension is a lossless compression format originally developed for the MAME (Multiple Arcade Machine Emulator) project.
The game itself is an import version of the original Metal Gear Solid, released for the PlayStation console in 1998. This particular variant is significant because it represents a distinct iteration of the game that may contain region-specific content, language options, or other unique features.
Benefit: Saves space, simplifies multi-track discs, and works perfectly for PS1. Metal Gear Solid -Spain- -Disc 1- -Rev 1-.chd
A PlayStation 1 Emulator: DuckStation is highly recommended for its "Fast Boot" and upscaling capabilities.
The Dub Delay: While MGS is famous for its Hollywood voice cast (David Hayter, Jennifer Hale), the Spanish release was initially subtitled only. A vocal minority in the Spanish gaming press demanded a full dub. It is believed that "Rev 1" might represent a late 1999 reprint or a specific Edición Española that included the fully localized voiceover for characters like Solid Snake and Otacon, a dub that is notoriously rare today. A vocal minority in the Spanish gaming press
Because the Spanish Rev 1 disc replaces English spoken codec calls with Spanish dubbing (for characters like Mei Ling and Naomi Hunter), the audio waveforms are different. Spanish prosody (rhythm, pitch) differs from English. Consequently, the FLAC compression ratio of a Spanish Rev 1 CHD is often slightly larger than the US Rev 0 because Spanish voice acting has a wider dynamic range, requiring less aggressive audio truncation.
-Rev 1-: This stands for Revision 1. In the era of physical discs, publishers would occasionally release newer pressings of a game to fix game-breaking bugs or minor glitches found in the initial "Rev 0" (launch) version. In the era of physical discs
Escape & Disc 1 Finale: