A surround check should play a sound on each real speaker in turn. Panning a stereo sound left and right only imitates direction, and proves nothing about the centre, the subwoofer or the surrounds.
- The system decides how many channels the browser gets. If it offers two, no web page can play surround, so set the output to 5.1 or 7.1 first.
- SystemCheck's test reads the channel count, and with six or eight sends a sound to one channel at a time: a burst of noise on each speaker and a 50 Hz tone on the subwoofer.
- The order of the surround pairs on 7.1 is the system's, so your ears are the result: say which speaker each sound came from.
The short answer
Set the system's output to 5.1 or 7.1, open the test, and play each channel. If a sound comes from the wrong speaker, two cables are swapped or the system orders the pairs differently; if a channel is silent, check that speaker's cable, the receiver's speaker setup and, for the subwoofer, its power and level.
Set the output to surround first
A browser plays as many channels as the system gives it. On a fresh install that is usually stereo.
- Windows: open Settings, System, Sound, More sound settings. Select the output, choose Configure, and pick 5.1 or 7.1.
- macOS: open Audio MIDI Setup, select the output, choose Configure Speakers, and set the surround layout.
- Over HDMI to a receiver or a TV, the receiver must also accept multichannel PCM.
- Reload the test page after any change, so the browser reads the new channel count.
How the test plays one speaker at a time
The browser reports the most output channels the system offers. With six or more, the page sets the output to that many channels, each kept separate, and routes each sound into one channel only, so it leaves on that speaker and nothing is panned or mixed. For 5.1 the order is front left, front right, centre, lfe (subwoofer), surround left, surround right, the order the Web Audio specification uses. Each speaker plays a 1.5-second burst of noise, which is easier to place by ear than a tone; the subwoofer plays 50 Hz, a tone inside every subwoofer's range.
With two channels offered the test plays left and right only and says why, rather than imitating surround.
Silent, swapped or missing
- Silent speaker: check its cable at both ends, and that the receiver's speaker setup lists it. A speaker set to None gets no sound.
- Silent subwoofer: check it is on and its level is not at the minimum.
- Wrong speaker: two cables are swapped, or on 7.1 the system orders the side and rear pairs differently. The system's own speaker test shows its order.
- Still only two channels in one browser: some browsers report two whatever the device is set to. Chrome and Edge pass the system's count through on the systems they read it from.
What it cannot check
A page cannot hear the room, so whether a speaker is wired right beyond what you hear is yours to judge. Speaker distances and levels belong to the receiver's own setup, usually with its microphone. Dolby Atmos height objects are not sent by a browser at all.
Terms used here
Questions
- Can headphones play 5.1 surround?
- Stereo headphones have two drivers. Virtual surround software can simulate direction on them, but a test that plays real channels will find two.
- Why does the test say only two channels when my receiver is 5.1?
- The system is giving the browser stereo. Set the output to 5.1 or 7.1 in the system's sound settings, check the receiver accepts multichannel PCM over HDMI, and reload.