Ah, the good old days when you could get really interesting chips at Radio Shack. They also had some of those various sound effects chips, complete with a really thick printed copy of the datasheet stapled to the back. I remember working on building up the example circuit from the datasheet for the sound synthesizer chip - basically a bazillion pots to access every feature of the chip. I even drew out a case design for it. But as a very young player at the time (I'm pretty sure this was even before I got my first computer), I rapidly ran out of funding to buy all those pots, plus I didn't realize the RS pots were pretty poor quality, nor did I have any concept of ordering them from anywhere else, since as a kid with no credit card, I had no idea how I would mail order from one of the advertisers in the electronics magazines. Took forever when I got my computer - I saved up my money, gave it to my Mom, who wrote a check, that took weeks to clear back then, even allowing that shipping across the US also took weeks back then.
The SPO256, I played with that one around 1988. I was building an 8 bit PC card with one with my friend for one of our classes. Wire wrappng it, even. Unfortunately we ran out of time and never got it completed. Unfortunately, our professor for that course, which was on speech synthesis and voice recognition, gave us materials well into the semester. First thing I had to do was read the ISA bus documentation to learn how to design the decoding circuitry, and then interface the SPO256. Kinda want to build one now, maybe just a USB interface version, even if modern speech synthesis has gone way beyond that classic chip.
If I was more into doing stuff with it, I'd maybe make it work with my first computer, which I still have and which still works. Problem is, it has no mass storage of any sort, not even cassette tape, so I'd have to build a workable interface for that first. As if I don't have enough other things to keep me busy these days.