How to use: Put on headphones or sit between your speakers. Play a test tone and use the controls to verify your stereo setup is balanced.
How to Test Balance
- Put on headphones or sit centered between speakers
- Click "Play Test Tone"
- Select "Left Only" - should hear only in left ear/speaker
- Select "Right Only" - should hear only in right ear/speaker
- Select "Both" - should hear equally from both sides
- Use "Panning Control" to test stereo field
What to Listen For
- • Volume balance: Both sides equally loud?
- • Clear separation: Left/right distinct?
- • Center image: "Both" mode sounds centered?
- • Smooth panning: Moves smoothly across stereo field?
- • No distortion: Clean tone at all positions?
Common Issues
- • Uneven volume: Check speaker placement or settings
- • Poor separation: Speakers too close together
- • Off-center image: Adjust listening position
- • Phase issues: Check speaker wiring
- • One side quiet: Cable or connection problem
Use Cases
- • Headphone testing: Verify both drivers work
- • Speaker setup: Balance stereo system
- • Home theater: Calibrate surround sound
- • Studio monitoring: Check mix position
- • Troubleshooting: Identify audio problems
Left Right Test FAQ
How do I check left and right on headphones?
Put the headphones on the right way round (most have a small L and R printed inside the headband or on the earcups), press Play Test Tone, then choose Left Only: you should hear the tone in your left ear only. Switch to Right Only and it should move to your right ear only. Both (Center) should sound like it sits in the middle of your head. If left and right come out the wrong way round, the headphones are on backwards or the channels are swapped somewhere in the chain.
Why is sound only coming from one side?
Work through the simple causes first. Check the balance slider in your sound settings (Windows Sound settings, macOS Sound output, Android and iPhone accessibility audio settings) and set it back to the centre. While you are there, check Mono Audio, an accessibility toggle that merges both channels: it will not silence a side, but with it on this test cannot separate left from right, because Left Only and Right Only both play in both ears. With wired headphones, push the plug all the way in: a jack that is half inserted often plays one side only. With Bluetooth earbuds, take both out and put them back in the case, because many pair in single-earbud mode when only one connects. On a stereo system, check that both speaker wires are connected and that left and right are not swapped at the amplifier. If one side stays silent on every device, the driver or cable is likely faulty.
For a fuller headphone check (channels, phase, frequency reach and buzz), use the headphone test. If both sides play but the stereo image sounds thin or hollow, run the speaker phase test to check the wiring polarity.