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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, use this audio channel test alongside your device’s balance and output settings.

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.