Level Matching
Definition
The practice of ensuring two audio signals are at the same perceived loudness before comparing them. Critical in A/B comparisons, plugin evaluation, and any context where a level difference could skew judgment.
In Simple Terms
Making two sounds the same volume before comparing them. Without this, the louder one always wins — your brain is wired to prefer louder. It's the most important rule of any A/B comparison.
In Practice
Before A/B comparing two mastering chains, the engineer adjusts both to the same integrated LUFS value, ensuring that any perceived quality difference is tonal or dynamic — not simply a loudness difference.
Common Confusion
The louder of two otherwise identical signals will almost always be perceived as better. Level matching eliminates this psychoacoustic bias and is non-negotiable for objective evaluation.
Sources & Verification
- Toole, F. E. — Sound Reproduction (3rd ed., level matching in evaluation)Routledge, 2017
- ITU-R BS.1116-3 — Methods for the subjective assessment of small impairments in audio systemsInternational Telecommunication Union, 2015
Last verified: 2026-05-05