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