Listen to the reference, mimic it with your voice, get scored.
Reference sound: a synthesised bell — a short, bright "ding" with two harmonic partials decaying over about a second.
This is an internal calibration tool. Audio is processed entirely in your browser; nothing is uploaded. The microphone permission is used only for the 3-second recording window and released immediately after.
Keyboard: Tab to move between controls, Space or Enter to activate.