Distortion is any undesired change in an audio signal between its input and output.
Distortion occurs when an audio signal is altered in a way that was not intended by the original source. Instead of reproducing sound accurately, the system introduces changes in amplitude, frequency, waveform shape, or timing. These changes create audible artifacts that affect clarity, intelligibility, and overall audio quality. Distortion can arise from various components in a signal chain, including microphones, amplifiers, loudspeakers, and the electronic devices that process, transmit, or reproduce audio.
In commercial and industrial environments, distortion is a critical performance factor. Systems used for paging, emergency notifications, public address functions, conferencing, and AV communication rely on clean audio to ensure messages are understood clearly. Even small amounts of distortion can impact speech intelligibility or cause listener fatigue in facilities where audio functions as a core communication tool.
There are several categories of distortion. Harmonic distortion adds unwanted overtones that were not part of the original signal. Intermodulation distortion creates additional frequencies based on interactions between multiple tones. Clipping distortion results when a device is pushed beyond its designed limits, causing the waveform to flatten or “clip.” Mechanical distortion in loudspeakers can occur when components such as the diaphragm, cone, or suspension exceed their linear operating range. Electrical distortion can result from poor connections, inadequate power supply regulation, or mismatched equipment.
Although high quality cable does not eliminate distortion caused by electronic devices or loudspeakers, reliable copper conductors and proper shielding help preserve signal integrity. Well-constructed audio cable minimizes interference and reduces opportunities for noise to enter the signal path before it reaches amplifiers or speakers.
Sometimes referred to as audio distortion or signal distortion.
The Audio Engineering Society (AES) and the International Electrotechnical Commission (IEC) provide guidelines and testing methods for measuring distortion in audio systems.
The concept of distortion became central to audio engineering in the early days of telecommunications and broadcasting. As systems advanced from analog to digital formats, new types of distortion were identified, measured, and addressed through improved circuitry and signal processing methods. Modern measurement tools allow engineers to quantify distortion precisely across a broad frequency range.