Surround Sound Test (5.1 & 7.1)

This tool uses the Web Audio API to address each speaker in your surround system on its own channel. When the page loads, it reads the maxChannelCount property of the audio destination, which tells it how many discrete output channels your device reports — 2 for plain stereo, 6 for 5.1, and 8 for 7.1. That number appears in the badge above the room map so you know what your browser can actually reach. When you tap a speaker, the tool builds a short signal chain: a sine wave oscillator feeds a gain node, and the gain node connects to one input of a ChannelMergerNode that matches your chosen layout. If enough output channels are available, the destination switches to explicit channel counting with discrete interpretation, so the tone reaches only the speaker you picked — nothing bleeds into the others. Front and surround channels play a 440 Hz tone, the center uses 550 Hz so it stands apart, and the subwoofer test drops to 40 Hz, low enough that you feel it more than hear it. On a stereo-only device the tool falls back to the browser's standard speaker mixing, so every test stays audible while the notice explains the downmix. The play-all sequence steps through the layout on a 1.8 second timer, the volume slider adjusts the gain node live, and every tone is generated locally — nothing is recorded or uploaded.