Booster Volume

What Is Audio Distortion?

Distortion is any unwanted alteration of a signal between source and ear. Several distinct mechanisms produce it, and identifying which one you are hearing determines whether the fix is a setting, a file, or new hardware.

The main types

Clipping distortion
Peaks flattened at the ceiling. Sounds like crackle or fizz on loud moments. Caused by too much gain somewhere in the chain.
Harmonic distortion
Extra frequencies at multiples of the original, added by any non-linear component. Small amounts are inaudible and some are even considered pleasant.
Intermodulation distortion
New frequencies at the sums and differences of the originals. Less musically related and generally more objectionable than harmonic distortion.
Mechanical distortion
A driver pushed beyond its physical excursion limit. Common when boosting bass on small speakers, and audible as buzzing or rattling.
Codec artefacts
Introduced by lossy compression at low bitrates. Often heard as a watery or swirling quality on cymbals and sibilance.

Finding the cause

  1. Reduce the volume

    If distortion disappears at lower levels, something in the chain is being overdriven. If it persists, the file is the likely source.

  2. Try different output hardware

    If it only occurs on one pair of headphones or speakers, that hardware is being pushed past its limit.

  3. Try a different file

    If only one file distorts, it was probably clipped before you ever received it.

Frequently asked questions

Is some distortion always present?

Yes. Every component adds a small amount. Well-designed equipment keeps it far below audibility.

Why does bass boost cause distortion?

Low frequencies carry a great deal of energy, so boosting them pushes both the digital signal and the physical driver hard. Small drivers reach their mechanical limit quickly.

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