Frequency ABX Test — Pitch Drill
Can you hear tiny 50, 20, 10 or 2 Hz pitch shifts around 1 kHz? Double-blind ABX trials measure your true threshold. Free in your browser, no download.
Protect your hearing. Start at a low volume. Never raise the volume to make a tone audible. Levels are shown in dBFS, relative to full scale — not SPL.
How it works
Double-blind ABX frequency discrimination test synthesizing pure tones around 1 kHz with exact Hertz shifts.
Understanding Frequency Discrimination
Pitch perception operates through two complementary mechanisms in the human auditory system:
- Place coding: The tonotopic mapping along the cochlea’s basilar membrane, where high frequencies resonate near the base and low frequencies travel to the apex.
- Temporal phase-locking: The auditory nerve fibers fire in synchrony with the periodic cycles of sound waves up to approximately 4–5 kHz.
Around 1000 Hz, the human ear is remarkably sensitive to microtonal shifts. While untrained listeners easily notice a 20 Hz or 50 Hz jump, critical listening practice allows audio engineers and musicians to identify differences as tiny as 1 Hz to 3 Hz.
Frequently asked questions
What is frequency difference limen (DLF)?
The Difference Limen for Frequency (DLF) is the smallest change in pure-tone frequency that an individual can detect. At 1 kHz, healthy human ears typically exhibit a DLF between 2 Hz and 6 Hz.
Does training improve frequency discrimination?
Yes. Psychoacoustic research demonstrates that active ear training drills significantly sharpen frequency discrimination, shrinking listener DLF by up to 50% through neuroplastic adaptation.
Why use pure sine waves for frequency testing?
Sine waves stimulate a localized group of hair cells along the basilar membrane without harmonic overtones, isolating pure tonotopic frequency discrimination.