How is audio so complicated lol? Can't they just quantify deviations from the ideal "The input signal moves through the wire with zero quality loss and the transducer makes it sound as it should."
Gross oversimplification lol, physics is still a thing that exists, for example. :P You would need a diaphragm with no mass, and a voice coil that could move so fast that it wouldn't be inaccurate to call its movement teleportation, that could also stop instantaneously, to make a transducer that reproduces everything flawlessly. And then an enclosure that doesn't forget it up. And then most likely several nuclear power plants to power whatever ridiculous reality-bending method you're using to accomplish a diaphragm with no mass.
Edit: You'd have to make the mathematical concept of zero excite air, basically. I don't think that's going to happen...uh...ever.