I haven't been able to set up the A4 for now, but I will do it this weekend and send it to you. The way Jeff made the BNS sing was by changing the pitch and making it say simple syllables.
There is a small chance that we might be able to access the sound mode of the Votrax soon. Pitermach and I both have BNS2000s, and we can record any sample of it you want. I will also be making recordings of all of the other devices I own.
The BNS that used the Doubletalk synthesizer was called Scholar and was sold by APH back in the day. This is, of course, the same synthesizer used on the Bookport and Millenium series of the BrailleLite. Like pitermach said, it had a lot of parameters that the Blazie OS did not expose, which you can verify by reading any of the Doubletalk manuals available on the RCSystems website.
The RC8650/60 both have the same voice. I actually like it, and I'm looking for someone who is trying to sell a used DoubleTalk. I might also try to find a way to hook up an RC8660 to a single-board computer such as a Raspberry Pi. It has been done before with Arduino. That might also be a way to get speech output from a Raspberry Pi without the audio issues, since the UART is recognized as a serial port I believe.
The Votrax SC-02/Artic SSI-263 was used in a bunch of devices, including all the Artic synthesizer models, the Blazie notetakers and Blazer embosser, the Aycom Accent line of synthesizers, the Kentucky pocketBraille, and the GW Micro Speakout. Apparently, Artic made it sound pretty decent, but I have never heard those actually talk. Does anyone have a sample of an Artic synthesizer?
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