Published on May 16, 2018 GRay Defender
via Atari Age

The heart of the unit is the SpeakJet--an amazing chip with phonetic speech, preset sounds and a five channel music synthesizer. All of these are controlled by the console via a serial interface emulated through the driver software.
Similar to chips used in 80s speech synthesizers but with extended capabilities, the speech retains a nice retro quality, making it a perfect partner for classic consoles.
Also onboard the AtariVox+ is 32K of non-volatile memory which can be used as a memory card. The flash memory will retain data without power for 200+ years.
An allocation scheme has been devised so that no file is ever overwritten, allowing many different games to store data on just one unit.
Dip Switch Settings
The AtariVox+ contains a bank of dip switches that allow you to select which mode the AtariVox+ will operate in:
AtariVox - for the Atari 2600 and 7800 (default setting)
VecVoice - for compatibility with earlier Vectrex speech synthesis - mainly for the speech-hacked version of Berzerk (Verzerk) and Y.A.S.I.
VecVox - for the Vectrex."
The SpeakJet has been used in a number of synth projects including the Flame Talking Synth and the Polaxix Emy eurorack module. See the SpeakJet label below for more.