Speaker Tester

About Speaker Tester

Speaker Tester helps you diagnose laptop and desktop speakers without installing extra software. Choose between a calibration tone or a smooth frequency sweep to check for distortion, rattles, or dead channels. The tool runs entirely in your browser and supports mono or stereo monitoring.

1. Pick a test type: 440 Hz pure tone for alignment or a customizable frequency sweep.
2. Select left, right, or stereo channels and adjust the output volume slider.
3. Click Play to begin the test; update frequency or sweep settings to suit your speakers.
4. Use the recent playback log to track what you tested and repeat specific runs.

How do I tell if my speakers are actually working?

Set 'Channel focus' to Stereo, leave 'Lock to concert A' on, and press Play. A working speaker pair produces a clean, steady 440 Hz tone — the same note as concert A. Silence on both sides usually means audio is muted at the OS level (check the volume mixer), the wrong output device is selected (Bluetooth headphones connected but covered up by another driver), or the browser has output muted. If you hear the tone from only one side, switch the focus to Left or Right to isolate which channel is dead.

How do I test left and right speakers (and headphones) separately?

Use the 'Channel focus' selector. 'Left' sends the tone only to the left speaker; 'Right' to the right; 'Stereo' to both. If your laptop has only one built-in speaker, both channels still produce sound but with reduced spatial separation — that's a hardware limitation, not a bug. To test true stereo, plug in headphones or a USB DAC; the channel focus then becomes a perfect left/right isolation test. If a tone comes out of the wrong side, you have a wiring or OS balance swap; if one side is silent, that driver, wire, or connector has failed — reseat the cable, try a different jack, and retest.

Why a 440 Hz tone specifically, and what should a sweep reveal?

440 Hz is concert A (A4) — the musical reference pitch the world is tuned to, and an excellent middle-of-the-band tone for evaluating speakers. It's pure enough (no harmonics) that any distortion you hear is the speaker, not the signal: if it sounds buzzy, rattly, or thin, that's a real speaker problem. A frequency sweep glides smoothly from a low pitch to a high one, exercising the whole driver, and is the fastest way to spot rattles (panel buzzing at a specific frequency), driver damage (sudden dropouts or distortion at certain pitches), or roll-off (the high end disappearing early). A healthy laptop speaker is usually audible from roughly 200 Hz up; a desktop with a subwoofer should hold down to 40–60 Hz.

How do I pinpoint the exact frequency where a rattle or buzz happens?

Run the frequency sweep and watch the live frequency readout — it tracks the oscillator in real time as it glides, so the instant you hear a panel rattle, driver buzz, or dropout you can read the exact Hz. Press 'Mark frequency' at that moment and the value is appended to the recent playback log so you can document it (e.g. 'rattle at 312 Hz') for a repair report. Slow the sweep down with a longer duration to make narrow resonances easier to catch.

Can I set a custom frequency for the test?

Yes. Turn off 'Lock to concert A (440 Hz)' and the frequency input becomes editable. Valid range is 20 Hz to 20 kHz — roughly the limits of human hearing. Useful test frequencies: 60 Hz for hum verification, 100 Hz to test subwoofers, 1 kHz as the audio engineering reference, 4 kHz to check mid/tweeter crossover, 10 kHz for high-end response, and 16 kHz to see if you (or your speakers) still hear the very top of the band. Almost nobody hears the absolute extremes: most laptops and phones cleanly roll off below 60–80 Hz, and high-frequency hearing drops about 1 kHz per decade after age twenty.

I hear distortion when I turn up the volume — is the speaker bad?

Possibly, but more often it's one of three things you can fix without replacing hardware. (1) Browser/OS volume too high — laptop speakers usually distort above ~70% of maximum because the amp is being asked to deliver more than the cone can handle. Drop the slider to 50% and listen again. (2) Wrong audio device — make sure your OS isn't routing output to a Bluetooth speaker that's already maxed. (3) Damaged cone or surround — a healthy speaker holds the tone clean across most of the volume range; distortion that starts at low volume is more likely a real hardware issue. We serve a clean Web Audio sine wave, so the signal itself is never the source of distortion.

Which browsers and devices support this tester, and why must I click first?

The tool uses the Web Audio API's OscillatorNode, which works in all modern browsers — Chrome, Edge, Firefox, and Safari, including iOS Safari. Browsers block audio from starting on its own, so an AudioContext stays suspended until your first interaction. If you ever see 'click then press Play again', that's the autoplay-unlock requirement: one tap or click on the page unlocks audio for the rest of the session. There is no maximum-output guard built into the browser, so keep system volume moderate to protect your hearing and your speakers. No microphone permission is requested — the tester only outputs sound, it never listens.

Is the audio being recorded or sent anywhere?

No. The tester generates the tone or sweep locally using the Web Audio API's OscillatorNode — the signal lives entirely in your browser's audio pipeline and is sent only to your speakers. Nothing is captured, recorded, or transmitted, and no microphone permission is requested. The 'Recent playback' log shows only what you played from this page and clears when you close the tab. The page itself still loads normal website assets (and may show ads or feedback prompts), so it isn't strictly request-free, but the test signal never leaves your device.