Audio Distortion Test

Play clean tones that should sound perfectly smooth, so crackling, buzzing, rattles and distortion from your speakers or headphones stand out. You judge what you hear; nothing is measured.

Lower your volume before starting, especially with headphones. Nothing plays until you press a button.

Test

A pure sine wave at one frequency. It should sound completely smooth and steady.

Frequency

A clean tone should sound perfectly smooth. Anything rough, buzzy, crackly or rattling is worth investigating. This is a listening test, not a measurement.

Stopped

Runs entirely in your browser. Test results, audio and video never leave your device.

Next steps

How to test speakers for distortion

  1. Lower your volume, choose Steady tone, pick 100 Hz, 440 Hz, 1 kHz or 3 kHz and press Play. The tone should sound pure and steady.
  2. Choose Level steps. A test chosen while another plays starts at once; otherwise press Play. The tone rises through six levels, from 10% to the full Volume setting, 2 seconds each; note the step where it starts to sound rough.
  3. Choose Slow sweep. One tone glides from 20 Hz to 20 kHz over 40 seconds; note the frequency shown when something rattles, buzzes or crackles.
  4. Choose Two tones. 1 kHz and 1.1 kHz play together and always sound a little rough, because they beat 100 times a second. A distinct low hum or extra notes that other speakers do not produce suggest intermodulation distortion.
  5. Press Stop and listen for hiss, hum or crackling that carries on. The page is silent then, so that noise comes from your equipment, its connections or another app; a faint hiss close to the speaker is normal on many systems.

What is audio distortion?

Audio distortion is an unwanted change to the shape of a sound wave, added by a speaker, headphone or amplifier and heard as roughness, buzzing, fuzz or crackling. It hides in music but stands out on a clean sine tone, which should sound perfectly smooth. Distortion that appears only when loud is often a limit being reached; distortion at every volume points to a fault.

Is my speaker blown?

A blown speaker usually sounds fuzzy, scratchy or buzzy on a clean tone at every volume, or one of its drivers makes no sound at all. A rattle at a single frequency or crackling that follows the cable usually has another cause. To be sure, play the same tone through another speaker or pair of headphones from the same device: if that one sounds clean, the fault is in the first speaker or its cable.

What you hear on a clean toneWhat it usually means
Fuzz, scraping or buzzing at every volume, worst on low tonesA damaged driver, such as a torn cone or a rubbing voice coil: likely blown
Silence from one driver while the rest of the speaker playsA broken voice coil, a loose wire or a failed crossover part for that driver
A rattle at one or two frequencies onlyA loose grille, panel or screw, or a nearby object vibrating: usually not blown. Hold that frequency in the Tone Generator and touch nearby objects to find it
Crackling that changes when you move the cable or plugA worn cable, plug or socket, not the speaker
Muffled or quiet sound after the speaker got wetWater in the grille rather than distortion. The Speaker Cleaner plays a tone that may help push droplets out

What this test can detect

  • Crackling or dropouts from a worn cable, plug, connector or driver.
  • Rattles and buzzing from loose grilles, panels or nearby objects, found with Slow sweep.
  • Roughness that starts above a certain level, found with Level steps.
  • A low hum or extra notes with Two tones that other speakers do not produce, a sign of intermodulation distortion.
  • Hiss, hum or noise that carries on after you press Stop.

How it works

Every test plays sine waves from the Web Audio API in both channels at once. Level steps play the tone at 10, 25, 40, 55 and 75 percent of your Volume setting, then the full setting, 2 seconds each; these are amplitudes, so the first step is 20 dB below the last. Slow sweep rises exponentially from 20 Hz to 20 kHz in 40 seconds. Two tones plays 1 kHz and 1.1 kHz at half level each.

The page’s signal peaks about 9 dB below digital full scale even at the top of the Volume slider, so distortion you hear is added further down the chain.

Limitations

  • This is a listening test. It cannot measure total harmonic distortion or give any number.
  • The tones always play in both channels together, so the page alone cannot show which speaker distorts.
  • Level steps are relative to the Volume slider, so how loud the top step gets also depends on your system volume.
  • Steady tone and Level steps offer 100 Hz, 440 Hz, 1 kHz and 3 kHz only, and the sweep range is fixed.
  • Keep the volume comfortable. A damaged driver or a loose part shows at moderate levels; turning up further mostly tires your ears and strains the speaker.

Frequently asked questions

Why do my speakers crackle at high volume?

Usually something in the chain has run out of headroom: the amplifier is clipping, or the speaker is moving as far as it can. Run Level steps; if roughness starts at the same step every time, you have found the limit, so keep the volume below it. Roughness that stays at low volume points to the speaker or its connection.

Why do my headphones crackle in one ear?

Often it is the cable, plug or socket: play a Steady tone and gently move the cable near each end, and if the crackle follows the movement, the cable or socket is at fault. On wireless earbuds, dropouts in one ear can come from the connection instead. To play a tone in one ear only, use the Headphone Test.

How do I find out which speaker is distorting?

Play the same frequency on one side at a time. These tests play in both channels together, so open the Tone Generator, choose Left or Right, and set the frequency where you heard the problem. You can also put your ear close to each speaker in turn.

Can a blown speaker be fixed?

Not with software. No tone or app can repair a damaged driver: a torn cone, a failed surround or a broken voice coil needs a repair shop or a replacement driver. With a passive driver disconnected, a multimeter across its terminals should read a few ohms; an open circuit means the voice coil or its wiring is broken.

Can my computer or phone cause the distortion?

Yes. Audio enhancements, loudness or bass boost effects, a system volume set to maximum, or a weak Bluetooth connection can all add roughness. Turn the effects off and try another source; if the speaker sounds clean there, the fault is in the first device or its settings.