As well as classic drum patterns the Casiotone 403 has some nice vintage analog keyboard tones. Short of circuit bending, there’s not really any way to manipulate those tones other than vibrato and sustain under the effects section. These are simple on or off settings, so there’s no depth, speed, or decay adjustments. You get what you’re given, but that’s what you’d expect from an instrument of this sort, and part of its charm.
I actually have used this keyboard for a couple of performances. Once at the May day festival in Minneapolis I played it with a group of kale wearing performers. During the parade we were joined by Wavy Gravy, so we gave him a mic and accompanied him for thirty minutes or so. There’s a lot more to this story that I won’t go into here, but in any case my favorite line that he used was, “Don’t eat the brown kale”. Afterward I had him sign my brown, wood grain Casiotone 403.