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Audio Channel Test: Left, Right and Stereo

Runs locally in your browser. Nothing is uploaded.

Web Audio tone controls

Generate a local tone, select its waveform and channel, and stop it instantly.

440 Hz · sine · both
Set device volume low before starting. The page never records audio.

This is an uncalibrated output and routing tool, not a hearing test. Browser, device, amplifier, speaker, and room response all affect what reaches you.

Last updated: July 29, 2026

Audio channel test: This audio channel test checks whether a browser, operating system, interface, and playback device preserve left, right, and centered stereo routing.

How this audio channel test works

Play the left, right, and both-channel controls in sequence at low volume. If needed, change frequency to avoid a room null or speaker crossover point. Stop before changing the output device.

How to read the results

A correct stereo path keeps the side signals isolated and places the both-channel signal near the center. Some crosstalk is normal in speakers because both ears hear both cabinets. Headphones provide a stricter isolation check.

Common causes of failed tests

Channel errors may start in the application mixer, operating-system balance, mono accessibility option, audio interface, cable breakout, receiver input, or physical speaker wiring.

Troubleshooting before you replace hardware

Disable mono audio for a stereo test, center the balance control, check interface routing software, and test headphones directly. Swap cables one stage at a time to locate where the channel changes.

For setup and buying context, see the tone generator, left/right speaker test, audio channel test, bass test, subwoofer test, and DTMF tone generator.

Frequently asked questions

What does the both-channel button test?

It sends the same tone to left and right, which should form a centered image in a balanced setup.

Can speakers have some channel bleed?

Yes. In a room, both ears hear both speakers; headphones isolate channels more clearly.

Does this support four waveforms?

Yes. Choose sine, square, triangle, or sawtooth.