Speaker & Headphone Test: Left/Right
Check left and right speakers or headphones, stereo panning, phase and bass with a 20 Hz to 20 kHz sweep. No voice clips, and a WAV test track to download.
Nothing playing. Start with your device volume low.
Left and right channels
Stereo and phase
In phase should sound solid and centred; out of phase diffuse and thin. The reverse means one speaker's wires are swapped.
Frequency sweep (bass and treble)
Surround channels
Your output's channel count is read when a sound first plays.
Download test track
A 16-bit, 48 kHz stereo WAV file with the tests below, for devices that cannot open this page.
| Starts at | What plays |
|---|
How to test your speakers or headphones
Start with your device volume low; the page’s own volume starts at 50%. Press Left, Centre and Right and listen for where each sound comes from. The speaker icons above the buttons light up with the channel that is playing. Choose pink noise, beeps or a chime as the test sound: noise is easiest to place, a chime is gentler on the ears.
Checking that left and right are not swapped
- Left must come only from your left: the left speaker as you face the screen, or the earcup marked L.
- Right must come only from the right.
- Centre plays both channels equally and should appear as one sound between the speakers or in the middle of your head. If it leans to one side, check the balance setting and the fit of your headphones.
- Pan sweep should glide smoothly from left to right and back, with no hole in the middle.
If Left comes from the right, the channels are swapped: headphones worn back to front, speaker cables exchanged at the amplifier, or a swap option in the sound driver. If Left and Right both come from both sides, the system is mono. Look for a Mono audio accessibility setting (Windows, macOS, Android and iOS all have one), or you are listening on a single speaker, as in many portable Bluetooth speakers and some phones.
Phase: in phase and out of phase
Both phase tests play the same pink noise in both channels. In phase sends identical signals and should sound solid and centred. Out of phase inverts the right channel, so the sound seems diffuse, hard to place, and thinner in the bass because the two speakers partly cancel. If In phase is the one that sounds vague and weak, one speaker is wired with + and − reversed. Swap the two wires on that speaker only.
Frequency sweep and bass
The sweep is a sine that rises logarithmically, so each octave takes the same time. Laptop and phone speakers produce little below about 150 Hz, compact bookshelf speakers reach about 50 to 60 Hz and a subwoofer 20 to 30 Hz. Press Mark when the tone becomes audible or disappears to note the frequency, and listen for rattles, which point to loose parts or resonances in the room. Many adults stop hearing somewhere above 14 to 16 kHz, which is normal. Keep the volume moderate: loud low tones can damage small drivers, and you may not notice how loud high tones are.
Surround channels
When the browser reports a 6- or 8-channel output, a surround section lists every channel in the standard WAVE order.
| Channel | 5.1 | 7.1 |
|---|---|---|
| 1, 2 | Front left, front right | Front left, front right |
| 3, 4 | Centre, LFE (subwoofer) | Centre, LFE (subwoofer) |
| 5, 6 | Surround left, right | Back left, right |
| 7, 8 | – | Side left, right |
A speaker other than the named one playing means the sound driver maps channels differently. Most systems report stereo unless 5.1 or 7.1 is selected in the operating system’s speaker setup.
Test track for other devices
Download test track saves the same tests as a 16-bit, 48 kHz stereo WAV file, for a car stereo, TV or Bluetooth speaker. The table under the button lists when each part starts.
Frequently asked questions
Is anything recorded or uploaded?
No. Every sound is generated by your browser’s Web Audio engine; there are no audio files to download and the page never uses the microphone. Nothing is sent or stored.
Why does the Left sound come out of both speakers?
Your output is mono. A Mono audio accessibility setting, a single-speaker device, or virtual surround and stereo widening effects in the sound driver all mix the channels together. Turn those off and test again.
Why is there no surround test for my home cinema?
Browsers only offer as many channels as the operating system reports. Set the output to 5.1 or 7.1 in your system’s sound settings and reload. Over Bluetooth or when the TV handles decoding, the browser usually sees stereo.
Is the out-of-phase test harmful to my speakers?
No. It plays the same noise with one channel inverted, which is common in real recordings. At a moderate volume it is as safe as any other sound.