Murilee sez, "Remember the first generation of cars with voice warnings, from the late-70s/early-80s era? The Datsun 810 was the first, and I've disassembled the voicebox from a junkyard unit. Turns out that Nissan used a tiny phonograph, complete with 3" record with 6 separate grooves (one for each message) and a precision solenoid-controlled stylus. All in a 3" cube. Coolest thing I've seen in a while."
1982 Datsun Voice Warning Box Used Tiny Phonograph Record, Just Like Moon Base Robots
(Thanks, Murilee!)