Audio Diagnostics Hub
TEST AUDIO METHODICALLY
A useful speaker or headphone check is more than hearing one beep. A silent channel, reversed left/right routing, a loose speaker enclosure, a driver that buzzes at one frequency, a Bluetooth path problem and an unusual phase relationship can all sound like “bad audio” while pointing to different next steps.
This guide connects GearCheck Lab’s browser-generated audio tools into a repeatable troubleshooting sequence. The tests generate low-level signals locally in your browser; they do not record your room or upload sound. They are designed to isolate audible symptoms—not to replace calibrated acoustic or electrical measurement equipment.
Start low: pure tones deserve caution
Set your system volume low before playing any test signal, especially through headphones or earbuds. Pure sine tones concentrate energy at one frequency and can feel more intense than ordinary music. High-frequency tones can be uncomfortable even when the volume control does not look extreme.
- Begin with a low system volume and a low in-tool level.
- Do not use a browser tone as a hearing test.
- Stop immediately if you feel discomfort, pressure, ringing or pain.
- Do not hold a loud tone on small speakers for long periods.
- When checking a rattle, use the lowest level that reproduces the symptom.
A practical speaker and headphone test sequence
Change one variable at a time. If you alter the output device, Bluetooth connection, operating-system balance and test frequency simultaneously, you lose the evidence that tells you which change affected the symptom.
- Confirm the correct output device and basic playback.
Before diagnosing hardware, verify the browser tab and operating system are not muted and the expected headphones, speakers or interface are selected. Use the Audio Test for a quick local output check. - Test left, right and centred output.
Use the Channel & Frequency Test. Left should be heard on the left, right on the right, and centred output should not unexpectedly disappear from one side. If a channel is reversed, check physical orientation, cables, operating-system balance/routing and audio-interface configuration before blaming a driver. - Try several moderate spot frequencies.
A single 440 Hz tone does not exercise the whole audible range. Compare low, mid and higher tones at a comfortable level. Listen for a side that disappears, becomes much quieter, buzzes or crackles only in one band. - Run a controlled sweep and note where a symptom starts.
The Speaker Sweep & Rattle Test moves through frequencies and lets you hold the current frequency. If a buzz appears at a repeatable point, stop the sweep, hold that frequency at low volume and inspect the speaker, enclosure, desk and nearby objects for resonance. - Use phase comparison only after channels are confirmed.
The Speaker Phase & Polarity Test compares an in-phase stereo reference with the right channel digitally inverted. With properly positioned speakers, the in-phase version often sounds more centred/solid while the inverted comparison may sound diffuse or hollow. Treat this as a listening clue, not electrical certification. - Compare another output path.
If practical, repeat the suspicious step with another pair of headphones, speakers, cable, USB interface or wired connection. A symptom that follows one physical device tells you something different from a symptom that follows every output connected to the computer.
Choose the audio diagnostic that matches the symptom
The focused tools deliberately overlap enough to confirm basic playback, but each one answers a different troubleshooting question.
Channel problems: routing before repair
If the left test plays from the right side, first check whether headphones are physically reversed and whether a cable, adapter, interface or operating-system routing setting is swapping channels. A browser can request left/right panning, but it cannot inspect how your hardware is wired after the signal leaves the computer.
If one side is silent across several frequencies, compare another output device. If the same computer plays both channels correctly through another device, the problem becomes more likely to be downstream in the original headphone/speaker/cable path.
A repeatable rattle is more useful than a vague “bad sound”
Mechanical rattles often become strongest in a narrow frequency band. During a sweep, note where the noise begins and ends. Use Hold Current at the lowest practical level, then gently check whether the sound changes when you move the speaker away from a wall, lift an object off the desk or lightly stabilise a loose enclosure panel.
Do not assume every rough sound is a blown driver. Furniture, laptop chassis parts, loose grilles, cable connectors and objects sitting near a speaker can resonate too. Repeating the same held tone after moving the device helps separate the speaker from its surroundings.
Read common observations like a troubleshooting signal
| Observation | What it may suggest | Useful next step |
|---|
| Left test is heard on the right | Physical orientation, routing, adapter/cable or channel assignment may be reversed. | Confirm headphone orientation and OS/interface channel mapping, then retest. |
| One side is silent at every tested frequency | Muted balance, bad connection, cable fault, interface routing or failed driver are possibilities. | Try another output device/cable and inspect balance settings. |
| Buzz appears at the same narrow frequency every run | A driver, enclosure or nearby object may be resonating. | Hold the frequency at low level and change physical placement one variable at a time. |
| Rattle only occurs at high volume | The test level itself may be overdriving the speaker or exciting cabinet vibration. | Reduce volume; do not use high-level browser tones as a stress test. |
| Bluetooth crackles but wired playback is clean | Wireless link, codec, interference or device power state may be involved. | Recharge/re-pair, reduce interference and compare again. |
| In-phase and inverted references sound very different on speakers | That is expected to some degree and is influenced by speaker position, room acoustics and wiring. | Use the difference as a comparison clue, not proof of electrical polarity. |
| The same defect is present on several different outputs | The source, OS audio path, browser, interface or content may be upstream of the individual speaker. | Compare another browser/app and review system audio processing. |
Speakers and headphones do not behave the same in a phase test
With two loudspeakers in a room, left and right channels physically combine in air, so relative polarity strongly affects the acoustic result at your listening position. Reflections, distance and speaker placement also matter. With headphones, each ear is driven much more independently, so the subjective change can be different and should not be interpreted exactly like a two-speaker wiring check.
The GearCheck phase tool creates a controlled digital reference: the same oscillator feeds both channels, then the right channel is inverted for the comparison. It does not measure the electrical polarity of a speaker terminal, cable or driver.
Frequency sweep results are listening observations, not a response graph
Human hearing sensitivity changes with frequency, and your room, device volume, headphone seal and speaker placement all change what seems louder. A browser sweep is excellent for locating a repeatable buzz, dropout or obvious channel difference. It is not a calibrated graph of frequency response.
If you need quantitative loudness, distortion, phase or frequency-response measurement, use calibrated hardware and measurement software designed for acoustic or electrical testing.
What browser audio diagnostics can and cannot establish
Strong use caseConfirming audible playback, left/right routing, repeatable rattles, obvious dropouts and differences between two output paths.
Useful comparisonWired vs Bluetooth, one headphone vs another, before/after cable changes, or the same held frequency before/after moving the speaker.
Needs instrumentsSound-pressure level, true frequency-response curves, harmonic distortion, electrical polarity, impedance and calibrated phase measurement.
The Web Audio API generates the signal inside the browser. From there it still passes through the operating system, drivers, audio interface or codec, amplifier and physical transducer. A clean browser result means the tested audible behavior looked normal under those conditions; it does not certify every part of that chain.
Make comparisons repeatable
- Keep system and in-tool volume unchanged between A/B comparisons.
- Use the same listening position when comparing speakers.
- Disable optional EQ/spatial enhancements if they are not part of what you are testing.
- For Bluetooth problems, note battery state and distance from the transmitter.
- Repeat a suspicious frequency instead of relying on one fast sweep pass.
- Test another cable or physical port before concluding a speaker driver has failed.
- When buying used gear, test at moderate—not abusive—volume.
Audio testing FAQ
Can GearCheck Lab tell me if my speaker is blown?
It can help you reproduce symptoms such as a silent channel, buzz, rattle or frequency-specific dropout. Those observations may be consistent with speaker damage, but a browser cannot inspect the driver or prove which internal part failed.
Why does the sweep sound louder at some frequencies?
Your ears, room, speaker/headphone response, placement and system processing all affect perceived loudness. Do not interpret perceived volume changes as a calibrated response curve.
Can I use the sweep to find the limit of my hearing?
No. GearCheck Lab’s tones are hardware-troubleshooting signals, not a medical or hearing-assessment tool. Hearing tests require controlled level calibration and appropriate clinical methodology.
What if only Bluetooth sounds bad?
Compare wired playback if the device supports it. A Bluetooth-only symptom can involve radio interference, codec behavior, battery/power state, pairing or the operating-system wireless stack rather than the speaker driver itself.
Does phase testing work with headphones?
You can hear the digital in-phase/out-of-phase comparison through headphones, but do not interpret it exactly like two speakers in a room. The acoustic interaction and ear-to-ear isolation are different.