Press Play and only the left speaker should make a sound. Switch to Right, then Stereo, and within ten seconds you know whether the channels are wired the right way round and whether one side has gone quiet. A dead side is often just the balance slider in your sound settings pushed all the way over. The two speakers on the screen react to the real signal in each channel, so you can see what the page sends even with the volume turned down.
What each test checks
- Left, Right and Stereo. Sound in one channel at a time, then in both. Pink noise is the easiest to locate by ear; you can also pick a steady 440 Hz tone or short beeps.
- Alternate. Jumps between left and right every second and a half, which helps when you are across the room moving a speaker and cannot reach the keyboard.
- Frequency sweep. A tone that climbs from 20 Hz to 20 kHz over twenty seconds. Listen for anything in the room that starts to buzz as the tone climbs, and note where the top end fades out. Most adults stop hearing it somewhere between 15 and 17 kHz.
- Bass. Steady low tones from 20 to 120 Hz for subwoofers and bass-heavy headphones. Laptop speakers usually go quiet below 100 to 150 Hz; that is a size limit, not a fault.
- Phase. The same noise in both speakers, switching every four seconds between in phase and out of phase. In phase, the sound is solid and sits between the speakers. Out of phase, it turns hollow and seems to come from everywhere. If you hear it the other way round, the plus and minus wires on one speaker are swapped.
Before you start
Turn the volume down, press Play, and raise it slowly: the sweep and the bass tones carry a lot of energy at full level. On a phone, take off a case that covers the speaker grille, and note that many phones have one real speaker plus the earpiece, so left and right depend on how you hold the phone. Bluetooth headphones sometimes stay in the mono headset mode used for calls; if both ears play the left test, switch the device back to its media profile.
What people use it for
New speakers or a new receiver
Confirm that left really is left and that the red and black wires sit on the correct terminals before anything goes on the wall.
Headphones and earbuds
Check each earbud on its own and catch a weak side early, before you blame the recording.
Subwoofer setup
Step through the bass tones to find where the subwoofer takes over from the main speakers and whether anything in the room starts to rattle.
Frequently asked questions
How do I test my speakers?
Open this page, press Play and go through the channel tests one by one. Each test should come only from the speaker it names. Then run the frequency sweep at a moderate volume and listen for distortion or rattling.
How do I test left and right earphones?
Put both earbuds in, choose Left and press Play: the sound should be in your left ear only. Then choose Right. If both sides play at once, mono audio is probably switched on in the accessibility settings of your phone or computer.
Why can’t I hear the lowest bass or the highest tones?
Both the hardware and your ears set limits. Laptop and phone speakers rarely reproduce anything below 100 to 150 Hz, and hearing above 15 to 17 kHz fades with age. A subwoofer or good headphones cover the low end; the top end depends on your ears.
Does the speaker test work on a phone?
Yes, in any current browser. Tap Play first, because browsers allow sound only after a tap. Phone speakers are small, so expect the bass test to be quiet.