right|thumb|Stereo-Pak player close up thumb|Stereo-Pak player with cartridge The Muntz Stereo-Pak, commonly known as the 4-track cartridge, is a magnetic tape sound recording cartridge technology.
right|thumb|Stereo-Pak player close up thumb|Stereo-Pak player with cartridge The Muntz Stereo-Pak, commonly known as the 4-track cartridge, is a magnetic tape sound recording cartridge technology.
The Stereo-Pak cartridge was inspired by the Fidelipac 2-track monaural (audio & cue tracks, later 3-track for stereo) tape cartridge system invented by George Eash in 1954 and used by radio broadcasters for commercials and jingles in 1959. The Stereo-Pak was adapted from the Fidelipac cartridge design by Earl "Madman" Muntz in 1962, in partnership with Eash, as a way to play pre-recorded tapes in cars.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).