Perception

These are the ones where your score is a threshold — the exact point where you stopped being able to tell. The last tone you can hear. The faintest colour difference you can spot. It's a strange feeling, walking right up to the edge of your own senses.

They're also where we have to be most careful. A hearing test is capped by your headphones and your volume. A colour test is capped by your panel and the light in the room. Push past what your gear can do and you're measuring the gear, not yourself — so these pages say which is which instead of handing you a limit and calling it yours.