Speech Synthesizer Accessory - Dismantled for reference and curiosity
In 1982 Mattel had the natty idea to release a ground breaking add-on for their Intellivision game console in the form of a dedicated voice synthesis module.
This made the Intellivision first game console to offer real-time human voices during game play. Rather than simply adding gratuitous bits of 'Get Ready' speech, the voice samples are designed to be an integrated part of supported games letting players know when to do a certain action, alert of danger, etc. The Intellivoice includes a volume control wheel that lets users independently set the voice volume without impacting the other game sounds coming from the television.
As seen below the Intellivoice plugs into the Intellivision's cartridge port and program cartridges are then inserted into the Intellivoice it. If you were ultra keen you can plug the ECS* into the Intellivision, the Intellivoice into the ECS and cartridges into the Intellivoice; also seen below. In fact you had to if you wanted to play 'Intellivision World Series Major League Baseball'; a technical breakthrough title in itself.
Unfortunately the add-on wasn't well received, mainly due to a very limited number of game titles; Space Spartans, Bomb Squad, B-17 Bomber, TRON: Solar Sailer and Intellivision World Series Major League Baseball. The latter being so limited in release it's almost not worth putting on the list. A sixth and final title targeted for kids called, 'Magic Carousel' was completed but never released.
As by 1983 Mattel had moved away from add-on hardware in favour of focusing on software, the Intellivoice quickly faded into obscurity. An additional two games, 'Woody Woodpecker' and 'Space Shuttle' were never completed even though the voice recordings had been made.
* see specific page on this site for the Intellivision Entertainment Computer System (ECS).