Surround Sound Test
A 5.1 and 7.1 surround sound test: a short burst of noise on each speaker in turn, lit on a room diagram, and a plain answer when only stereo is available.
Turn your device volume down first.
Start quiet. Turn your device volume down before you play anything, then raise it slowly.
That is a high setting. Lower it before low or high tones, and never raise it with headphones on your ears.
How to use the surround sound test
The box at the top of this surround sound test says how many output channels your browser reports. With 6 or more, pick 5.1 or 7.1 (7.1 needs 8 channels), then press a speaker button to play a burst of pink noise on that speaker only. Play all in order walks around the room: front left, center, front right, the surrounds, and the subwoofer last; turn on Loop to keep going while you check levels from your seat. The diagram lights the speaker that should be playing.
Keyboard: Space plays all speakers in order, Esc stops.
How a web page reaches each speaker
The W3C Web Audio specification lets a page ask how many channels the audio hardware can take (maxChannelCount) and then send each channel separately. The channel order is fixed by the specification, so each button of this 5.1 surround sound test goes to a known channel:
| Channel | 5.1 | 7.1 |
|---|---|---|
| 1 | Front left | Front left |
| 2 | Front right | Front right |
| 3 | Center | Center |
| 4 | Subwoofer (LFE) | Subwoofer (LFE) |
| 5 | Surround left | Rear surround left |
| 6 | Surround right | Rear surround right |
| 7 | Surround left (side) | |
| 8 | Surround right (side) |
For 7.1 the specification lists the back pair before the side pair, so channels 5 and 6 are the rear surrounds and 7 and 8 the side surrounds. The subwoofer burst is filtered below 120 Hz, the range the LFE channel carries. If a burst comes from the wrong speaker, check the speaker setup in your receiver or the cables to it.
If the test says 2 channels
The number of channels comes from the audio hardware as your operating system presents it. If the system output is set to stereo, or the HDMI link to the TV or receiver only offers 2 channels, the browser reports 2, even when more speakers are connected. Set the output to 5.1 or 7.1 in your computer's sound settings and reload the page.
With only 2 channels, the test still runs a stereo version: front left, front right and both together. A stereo signal does not light the other speakers on its own: when the Web Audio specification up-mixes stereo to 5.1, the center, subwoofer and surround channels stay silent. If those speakers play anyway, your receiver is adding them.
Where each speaker should be
Dolby's home theater speaker guides place the speakers around one central seat, at ear height unless noted otherwise:
| Speaker | 5.1 | 7.1 |
|---|---|---|
| Front left and right | 22 to 30 degrees from center | 22 to 30 degrees |
| Center | 0 degrees, at the screen | 0 degrees |
| Surround left and right | 110 to 120 degrees | 90 to 110 degrees |
| Rear surround left and right | none | 135 to 150 degrees |
The first number of a layout is the count of standard ear-level speakers and the number after the dot is the count of subwoofers.
Dolby Atmos test: what a browser cannot do
In a Dolby Atmos layout such as 5.1.2 or 7.1.4, the third number is the count of height speakers, installed in the ceiling or firing upward to bounce sound off it, and sound can be placed and moved anywhere in the dome around you. This page plays plain audio channels, not a Dolby Atmos signal, so it cannot test the height speakers or moving sound objects. Use it to confirm that every ear-level speaker and the subwoofer are connected and in the right place, then play Atmos content from a source that supports it. Low bass response is easier to judge with the bass test, and picture to sound lag with the audio delay test.
More for sound check: Mic Test · Sound Test · Speaker Test · Headphone Test · Left Right Test · Bass Test · Audio Delay Test · Speaker Cleaner · Tone Generator
Building a home theater? Check the TV size and viewing distance chart.
Questions
Why does the test say my browser has 2 channels when I have a 5.1 system?
The browser reports what the operating system offers. Set the audio output to 5.1 or 7.1 in your sound settings, check that the HDMI or optical link carries more than 2 channels, and reload.
What does the .1 in 5.1 mean?
The number after the dot is the number of subwoofers. A 5.1 system has five ear-level speakers and one subwoofer.
Can I run a Dolby Atmos test in a browser?
Not fully. A web page can address separate channels but does not produce a Dolby Atmos signal, so height speakers and moving objects cannot be tested here.
Which browsers can play 5.1 or 7.1?
It depends on the browser, the operating system and the output device together. The box at the top shows what your setup reports right now.