Reference tones used to calibrate the level are called what?

• A. Line up tones
• B. Reference tones
• C. Calibration tones
• D. Test tones

Answer: (D)

The idea being tested is using a known signal to verify and set audio levels across gear. A test tone is specifically a signal created to test the chain—meters, preamps, fader levels, and speaker response—so you can measure exactly what the system reproduces and adjust to a known reference. This makes it the most precise, widely used term for calibrating level in practice. While terms like reference tones or calibration tones describe the purpose, engineers typically refer to the actual signal used for this quick check as a test tone, because it’s designed to test and confirm performance in a repeatable way. Line up tones aren’t typically used for this level-calibration context, so the term that best matches the purpose and common usage is test tones.