Apple II Plus, Apple IIe and Apple IIGS Echo+ Speech Synthesizer with Software

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"FROM THE INTERNET:
In the 1980s two other popular brands were the Echo II (slot-based) and Cricket (for the modem port on the IIc) synthesizers, made by Street Electronics. These latter also included the ability to produce a robotic voice, a female voice, sound effects, and stereo music. Some games released at the time had enhanced sound output when one of these two devices were detected. For speech reproduction, they used a method of accepting ASCII text from the computer in the form of “phonemes” to describe and produce voice through a built-in speaker. They used this approach because English words have a variety of pronunciation depending on their context. Properly programmed, the voice synthesizers could pronounce the word “root” to rhyme with either “boot” or “foot”. It wasn't until the IIGS came out with the built-in capability of speech reproduction (via the Ensoniq chip) that software making use of that feature became available in any quantity."