Amplitude
Definition
The magnitude of a sound wave's displacement from its resting position, directly corresponding to the intensity of the sound. Higher amplitude means a louder signal. In digital audio, amplitude is represented as numerical sample values within the range defined by the bit depth.
In Simple Terms
How big the sound wave is — which translates directly to how loud it is. A whisper has low amplitude; a scream has high amplitude. Every fader, gain knob, and volume control you touch is adjusting amplitude.
In Practice
A microphone captures a vocalist's performance as variations in amplitude over time. The louder the singer projects, the greater the amplitude of the signal entering the preamp.
Sources & Verification
- Rossing, T. D., Moore, F. R. & Wheeler, P. A. — The Science of Sound (3rd ed.)Pearson, 2001
- Rumsey, F. & McCormick, T. — Sound and Recording: An Introduction (8th ed.)Routledge, 2021
Last verified: 2026-05-05