Have you ever heard of this model? It was my first encounter, never seen it before and after, but i bought it because price was decent. Also the google gives not many records as the name is confused with the new model CTX 870 in.
It seems like the same family as CTK 630, so the mid 90s. Wikipedia says it's 1995 year. But it sounds for me better than the CTK 630 which had - well i don't know, very bad and noisy DAC? It sounded thin, cold, worse than many earlier Casio Keyboards like CTK 750 (1994), CTK 1000 (1993). Fortunately for my ear CT 870 sounds quite nice and comparable to CTK 750.
Highlights:
- Joystick for pitch-bend and modulation
- portamento button
- built in 3 reverbs
- oriental presets: Erhu, Zeng, Jiang Qin, Dizi, Sheng
<aybe it was made for the Asian markets? Other Casios from the era seems much more popular. Of course it was higher, more pricey model, so it's normal its not as common as the cheaper ones.
In therms of effects, its a step back from the CTK 750 which had not only reverbs but also delays, choruses, rotary etc. But you still can use split and layer at the same time, playing 4 voices at once (starting point of polyphony is 24).
I think i will made some video of this on my youtube channel Keyboarder Hoarder