The secret to successful demos with early speech synthesizers (like the Federal Screw Works "Votrax VS-6" -- yes, that was the company), was to have a constrained vocabulary where people would know pretty much what to expect. That made the relatively poor voice quality much easier to recognize. For my UCLA Touch Tone Unix version of ADVENTURE, the responses were pretty well know. UCLA graduate students would play the game on payphones in Westwood while waiting for pizzas, confusing other patrons by yelling out suddenly "I released the bird!" I learned early on that most people were far more amused than I had anticipated by my mapping of ASCII BEL (control-G) to the utterance "bing bing bing."
The system I came up with in those early days for mapping phone Touch Tone digits to ASCII for input was adopted with some minor modifications by Digital Equipment Corp. (DEC) DECtalk.
When I did speech synthesis demos with the Votrax, I found the best approach was to let people type in their own text that they wanted to hear. This guaranteed they'd recognize it, no matter how poor the actual voice quality. Sort of like the old "reverse speech" claims -- the brain is really good at pulling at patterns from chaos. Everyone loved it.
As you might guess, the most common inputs were various obscenities. I hand-tuned the text to phoneme files to handle them especially well. -L
@robryk There were even escapes for control characters, so you could enter ^C, etc. Pretty useful sometimes!
@robryk And there were ways to enter Q and Z of course, which most phones didn't show and still don't. Though a phone I use sitting here right next to me DOES have both on there!
@robryk LOL (actually, I just did a loud "guffaw"). No doubt it's online somewhere still, my paper trail online goes back to the early 70s or so, though I don't know offhand where and a quick search doesn't find it. No doubt I covered it in my original Usenix presentation of Touch Tone Unix, but I haven't seen that online in many years.
But as I recall, and I think this is accurate, it took two pushes to choose a letter. The first push would choose the three-group, and the second push would pick the position. So I believe "U" would be 8-2. Then I had a "cheat sheet" for users that defined how to escape (using */#) for case changes, numbers, special characters, etc. This sounds right to me.