How the test works
The island has two rows of buttons. The first picks the channel: left, right or both. The second picks the signal: a steady 440 Hz tone, a sweep that glides from 20 Hz to 20 kHz over twenty seconds and starts over, and a bass sweep that covers only 20 to 200 Hz in ten seconds. Press Play and the sound starts; the lamps marked L and R light up for the channels that carry signal, the trace shows the waveform being sent to the output, and during a sweep the frequency of the moment is written in the corner. You can change the channel and the signal while the sound plays, and every check you hear is added to the list. Press Stop when you are done.
The sound is made inside the browser with the Web Audio API and goes straight to whatever output your system has selected: built-in speakers, a USB or Bluetooth speaker, a monitor's speakers over HDMI. Nothing is recorded and no microphone is used. The trace on the panel shows the signal being generated, not what the speaker reproduces; the browser has no way to listen back.
What the result means
The result card counts the checks you played out of five: left, right, both, sweep and bass. It is a record of what was played, not a verdict on the speakers. The verdict is yours, and here is what to listen for.
- Left plays on the left, right on the right. The wiring and the balance are correct.
- A channel is silent. Either the speaker or its cable has failed, or the balance in the operating system is turned all the way to one side. Check the balance first: it is free.
- Both sides play, but the sound is thin when both are selected. A speaker wired with reversed polarity cancels the bass of the other. Swap the two wires on one speaker and try again.
- The sweep drops out and comes back. A gap in the middle of the range means a crossover or a driver problem; a limit at the bottom is normal and depends on the size of the speaker.
- A rattle at one frequency. Something is resonating; see the FAQ.
What to do if something is wrong
Rule out the settings before the hardware. In the sound settings of your system, set the balance to the centre, disable any spatial sound, loudness equalisation or bass boost, and select the output device you actually want to test: on a laptop with a monitor attached, the browser may be playing through the monitor. On Bluetooth speakers, check that the speaker is not in a mono mode that merges both channels.
Then swap. If the right channel is silent, swap the left and right cables at the amplifier or at the computer: if the silence moves with the cable, the cable or the source is at fault; if it stays with the speaker, the speaker is. On built-in laptop speakers, try a pair of headphones in the headphone test: if the headphones play both sides, the amplifier is fine and the speaker itself has failed.
When to return or claim the warranty
A new speaker set with a dead channel, a permanent rattle or a channel that cuts in and out is defective and should be exchanged within the return window. For a warranty claim, note which check fails and at what frequency the rattle appears; the technician will repeat exactly this test. Speakers damaged by playing them at full volume with a clipping amplifier, by liquid or by a fall are usually excluded, and so is the normal bass limit of a small speaker, which is a matter of physics and not a fault.
Frequently asked questions
The tone plays on the wrong side. Is the speaker broken?
Almost never. Swapped sides mean the left and right speakers are wired or placed the wrong way round, or a balance setting in the operating system is off centre. On a laptop the left channel should come from the speaker nearest the left of the keyboard. Swap the cables or the speakers, check the balance slider, and run the test again.
Why does the sweep go silent below a certain frequency?
Small speakers cannot move enough air to reproduce deep bass. Laptop and phone speakers usually fall silent somewhere between 150 and 300 Hz, small desktop speakers around 80 to 100 Hz, and a subwoofer reaches 30 to 40 Hz. The readout in the corner shows the frequency at any moment, so note where the sound appears; that is the practical low limit of the speaker, not a fault.
I hear a buzz or rattle during the bass sweep. What is it?
A rattle at one particular frequency is usually something resonating: a loose grille, a cable touching the cabinet, an object on the desk, or the laptop lid. A buzz that follows the tone across many frequencies points to a torn cone or a loose voice coil in the speaker itself. Turn the volume down, move the speaker, and repeat the bass sweep to tell the two apart.
Why can I not hear the top of the sweep?
Hearing above 15 to 16 kHz fades with age and with years of loud listening, so a sweep that seems to end early is often the ear, not the speaker. Ask a younger person to listen, or point a phone with a spectrum analyser app at the speaker: it shows the peak moving up even when you no longer hear it. Many small speakers also roll off above 15 kHz by design.
Does this test measure loudness or frequency response?
No. The browser plays a signal it generates and cannot hear what comes out of the speaker, so the page cannot rate loudness, distortion or frequency response. The result card counts which checks you played. For a measurement you need a microphone and a calibrated tool; this page is for finding a dead channel, a swapped side, a buzzing driver and the bass limit by ear.
No sound at all on my iPhone or iPad?
Check the ring/silent switch on the side first: with it set to silent, Safari plays no web audio at all, whatever the volume slider says. Then raise the media volume with the side buttons while the tone is playing, since the buttons change the ringer volume when nothing plays. If a Bluetooth device is connected, the sound goes there, not to the built-in speakers.