Frequency Check — Low & High Walk

This frequency check plays stepped sine tones in order, nine low steps from 20 to 200 Hz or ten high steps from 2 to 20 kHz, and builds a heard map as you mark each one. It runs entirely in your browser for screening and equipment checks, nothing is uploaded, and no sound plays until you press Play step.

How to use it

1. Pick a walk. Low 20–200 Hz uses nine steps and High 2–20 kHz uses ten. The mode buttons swap the step list immediately and restore the answers saved for that walk if you have run it before.
2. Set up before you start. Use headphones in a quiet room, choose a comfortable volume, and then leave that volume alone for the whole walk.
3. Press Play step. Each step is one 1.2-second sine at a fixed gain of 0.25, which is −12.0 dBFS, with a 20 ms attack and an 80 ms release so it starts and ends without a click.
4. Answer heard or not heard. I heard it and I did not hear it both record the answer and advance to the next step automatically.
5. Read the map and counters. The current step is outlined, heard steps show as mint chips, missed steps appear muted, and the readout tracks walk, step number, frequency, play state and heard count.
6. Finish and repeat. When every step is answered the walk is complete; Restart walk clears the answers and runs it again. The saved line keeps the last run in this browser with a timestamp and a heard count, and Clear saved walk removes it.

The two step lists

The walk uses fixed, evenly spaced steps rather than a sweep, so every answer maps to one exact frequency in hertz.

Walk	Steps	Frequencies
Low	9	20, 30, 40, 50, 60, 80, 100, 150 and 200 Hz
High	10	2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 kHz

What each frequency means in the room and in the ear

Wavelength decides how a tone behaves in a room and in a driver, and at 20 °C it is λ = 343 / f meters. A 20 Hz tone has a wavelength longer than a typical living room, so you are listening to pressure changes rather than to a wave that travels across the space.

Frequency	Wavelength at 20 °C	What that implies
20 Hz	17.2 m	Longer than most rooms; small drivers cannot move enough air to reproduce it
100 Hz	3.43 m	Comparable to room dimensions, so standing waves shape what you hear
1 kHz	343 mm	The reference region where most ears are close to their most sensitive
10 kHz	34.3 mm	Easily absorbed by soft furnishings and blocked by obstacles close to the ear
15 kHz	22.9 mm	Tests how cleanly a headphone driver moves at high speed
20 kHz	17.2 mm	The top of the commonly quoted range, inaudible for many adults

Sensitivity across that range is not uniform. Equal-loudness contours such as ISO 226 describe how much level the ear needs at each frequency for the same perceived loudness, and they show a steep rise in the level required at the bottom end, a minimum around 3 to 4 kHz, and another rise above the midrange. That is why the low walk often needs more level than the high walk to feel equally loud, and why the fixed gain here is deliberately modest.

Missing tone or inaudible tone?

A silent step can mean the system produced nothing or that your ear did not register what it produced, and the way to separate the two is to change one variable at a time.

• Swap the output device. Repeat the step on headphones and on speakers. If it sounds on one and not the other, the missing tone is a device limit.
• Expect low-frequency roll-off. Most phone and laptop speakers fall away steeply below 150–300 Hz, so silence at 20 to 40 Hz on a phone says nothing about hearing.
• Listen for harmonics. A speaker that cannot reproduce 40 Hz usually still produces 80 Hz and 120 Hz, so a faint tone an octave or two above the step means the fundamental is absent, not that you are deaf to it.
• Try a wired path. Many Bluetooth codecs band-limit the top octave, so a missing 18 or 20 kHz step over Bluetooth may appear with a cable.
• Keep the level fixed. The walk presents each step once at the same gain. If a step only appears after a large volume increase, note it as a level-dependent result rather than a threshold.
• Compare ears if you want to. The page sends the same signal to both channels, so mute one side in your system mixer or use a single earcup.
• Repeat on another day. Congestion, background noise and room changes all move the result around; a single missed step is not a finding.

The high end deserves patience. Sensitivity above 12 to 14 kHz commonly declines with age, and a missing top step is a normal variation rather than a defect. If steps are consistently missing across devices at sensible levels, or if your hearing concerns you, book a test with an audiologist. This page is informative only and never a diagnosis.

Accuracy, limits and troubleshooting

• One presentation at a fixed level. A missed step means “not audible at this level today”, not “damaged at this frequency”. Threshold measurement is the job of the hearing test pages.
• No calibration. Levels are dBFS relative to full scale, so results cannot be compared with an audiogram or trusted across different sessions and devices.
• Speaker and headphone limits. Small drivers dominate the low walk and Bluetooth paths shape the high walk; a full-range pair of headphones gives the most useful coverage.
• System processing. Equalizer settings, loudness compensation and enhancement suites can change specific bands before the tone reaches your ears. Reset them for a clean run.
• Sample-rate conversion. Browsers may resample to 44.1 or 48 kHz; pitch is unaffected, but the anti-aliasing filter on some paths softens the very top step.
• Saved state is local. The timestamped walk lives in this browser’s storage only. Clearing site data removes it, and nothing is uploaded at any point.
• Screening boundary. This is an educational check for curiosity and equipment testing, not a clinical procedure, and it does not replace a calibrated audiogram.

Related tools

• High-Frequency Hearing Test: staircase measurement of the top octaves from 8 to 22 kHz.
• Low-Frequency Hearing Test: the same guided approach focused on 10 to 100 Hz.
• Hearing Test: per-frequency threshold staircases across 125 Hz to 8 kHz with an audiogram-style display.
• Learn: normal human hearing range: the numbers behind the 20 Hz to 20 kHz range and how age changes them.

Aliases covered on this page: frequency check, frequency response check, low frequency check, high frequency check, and audible frequency check.