This one is about the optoisolator. I never managed to find one with two outputs.
As for that chip, I know it says "audio" but I think that refers to the log taper. I actually want a linear taper. Does the word "audio" refer to the taper, or to it's ability to be used in audio applications? I mean I know it's a log taper but does that necessarily mean it is suited for audio applications?
Oh sorry, also the first issue I ran into was that my circuit uses 9v. So the digipot would need to be suited for that.