Unlike modern VSTs, the SC-55 was a ROMpler. It played back compressed samples stored on a chip. Early Soundfonts were essentially "recordings of recordings." They lacked the specific synthesis behaviors of the original hardware, such as:

: Correcting the mapping of drum hits, such as moving the Kick Drum from the 36th key to the 35th key to match General MIDI standards. Multi-Velocity Layers

The search for a "full paper" on a fixed Roland Sound Canvas SC-55 SoundFont