Sounds like a great challenge—let’s sketch the core first, then add a few tweak‑modules so the tone can shift on the fly. Think tiny amps, a micro‑controller for controls, and a quick‑swap sound chip. Keep the form factor light, use a battery that lasts a decent chunk, and add a button that switches modes. We’ll get a pocket‑sized wizard that can go from plink to wail in a snap.