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Perception & Psychoacoustics

How the ear and brain process sound: critical bands, masking, loudness perception, and the auditory mechanisms underneath every mixing and arrangement decision on this site.

• What Is Auditory Fatigue?

  Learn what auditory fatigue is, why your ears become less objective during long mixing sessions, and how psychoacoustics explains the need for regular listening breaks.

• What Is Auditory Scene Analysis? How Your Brain Separates Instruments in a Mix

  Learn how auditory scene analysis allows the brain to separate instruments into distinct sound sources using timing, pitch, timbre and location. Discover why great mixes are easier to understand.

• What Are Critical Bands? The Foundation of Frequency Masking

  Discover what critical bands are, why the cochlea divides sound into overlapping frequency regions, and how this explains frequency masking, EQ decisions, and cleaner mixes.

• Can You Train Your Hearing Every Day?

  Can mixing engineers improve their hearing through daily practice? Learn how deliberate listening, comparison, and repetition can build more reliable mixing judgment.

• What Are Equal-Loudness Contours? Why Your Mix Sounds Different at Different Volumes

  Learn how equal-loudness contours explain why a mix changes character at different listening levels, why professionals reference around 75-85 dB SPL, and how this improves mix translation.

• Why Frequency Charts Can Be Misleading

  Learn why frequency charts are useful references but poor mixing guides, and how psychoacoustics explains why music should be balanced by perception instead of memorized numbers.

• What Is Frequency Masking?

  Frequency masking happens when one sound makes another harder to hear because both occupy the same part of the frequency spectrum. Learn how critical bands and the upward spread of masking shape mix clarity, and why EQ is only one way to fix it.

• What Is the Haas Effect?

  Learn what the Haas Effect, also known as the precedence effect, is and why it makes sounds appear wider without creating a distinct echo. Discover the psychoacoustics behind stereo perception.

• How to Protect Your Hearing While Mixing on Headphones

  Headphones are powerful mixing tools, but your ears are the most important part of your monitoring system. Learn practical ways to manage level, EQ, breaks, and headphone comfort during long mixing sessions.

• How to Listen to Music as a Mixing Engineer

  Learn how to listen to music like a mixing engineer without losing the ability to enjoy it. Develop a listening process that separates arrangement, performance, tone, balance, depth and translation.

• What Are Interaural Time and Level Differences?

  Learn how Interaural Time Differences (ITD) and Interaural Level Differences (ILD) allow humans to locate sound. Discover the psychoacoustic principles behind stereo imaging and localization.

• What Is a Just-Noticeable Difference?

  Learn what a Just-Noticeable Difference (JND) is, how Weber's Law explains human hearing, and why some EQ and level changes are audible while others are not.

• What Is the Missing Fundamental?

  Discover the psychoacoustic phenomenon known as the missing fundamental. Learn why listeners can perceive bass even when the lowest frequency is absent and how this affects mixing and playback.

• What Is Temporal Masking? Why Timing Matters as Much as EQ

  Discover temporal masking, the psychoacoustic principle that explains why sounds can hide each other across time. Learn how it affects punch, clarity and rhythm in a mix.

• What Is Upward Spread of Masking?

  Upward spread of masking explains why low-mid buildup has a disproportionately large effect on mix clarity. Learn how the cochlea creates this effect, why small EQ moves can sound bigger than they measure, and why arrangement matters more than EQ.

• Why Should You Mix at 80 dB SPL?

  Learn why many mix engineers monitor around 75–85 dB SPL, how equal-loudness contours affect your decisions, and why a consistent reference level improves mix translation.