Speaker and headphone test
Verify every channel sounds where it should, that no wires are crossed and how far your gear reaches with a 20 Hz to 20 kHz sweep. Nothing to install.
Channels
A 3-second tone on the chosen channel. With headphones the split is unambiguous; on speakers watch the stereo image.
Phase
In phase sounds full and centered; out of phase sounds thin and hollow with almost no bass — the classic telltale of a swapped wire or a reversed speaker.
Sweep 20 Hz → 20 kHz (20 s)
Turn the volume down first. The felt-not-heard bass is the subwoofer; adult hearing fades around 15-17 kHz, and the top-end buzz is usually your gear's limit, not your ears.
Channel quiz
A tone plays on a random channel; guess which.
All audio is generated in your browser with Web Audio (sine oscillator and per-channel mixing). Use headphones to isolate channels and keep the volume moderate: loud high-frequency sweeps hurt ears and tweeters.
Built by
Miguel Ángel Colorado Marin (MACM)
Built by
Miguel Ángel Colorado Marin (MACM)
Full-Stack Developer · Guadalajara, España
I develop web apps, digital tools and full projects — from design to deployment.
An audio system can hum along for months with a fault nobody pins down: the dead right channel from a dirty jack, two speakers wired out of phase leaving the bass hollow, or a dead tweeter you only notice when the highs are gone. This diagnostic goes past the classic "buzz each channel": it plays per-channel tones to verify placement, includes a real phase test (the same tone in phase versus the right channel inverted — the bass collapses if anything is crossed), generates a 20 Hz to 20 kHz sweep with the frequency on screen to catch resonances, dead tweeters or woofer dropouts, and finishes with a channel quiz to train your ear. Everything is synthesized in your browser with Web Audio: no files, no downloads.
Features
- ✓Per-channel tone: left, right or both, with native Web Audio
- ✓Live phase test: both channels in phase versus the right one inverted
- ✓20 Hz to 20 kHz sweep in 20 seconds with visible frequency
- ✓Adjustable fixed tone to hunt buzzes and resonances
- ✓Channel quiz: guess which headphone plays the tone and track your score
How do I test my speakers online?
- 1
Turn the volume down
Especially before the sweep: loud high tones hurt ears and tweeters.
- 2
Test each channel
Left, right and both: with headphones you'll know instantly if a side is dead.
- 3
Check the phase
Alternate in phase and out of phase: if the bass fades out of phase, a wire is swapped.
- 4
Run the sweep
20 seconds from 20 Hz to 20 kHz, noting every frequency where sound drops or buzzes.
Frequently asked questions
What is the phase test for?
If two speakers are wired with reversed polarity they both play but in counterphase: bass cancels and sound turns hollow and off-center. Alternating in-phase and out-of-phase lets you hear the difference: if out-of-phase sounds fuller, you have a swapped wire.
Why do I stop hearing the sweep above 15 kHz?
That's normal: hearing sharpness drops with age and adults typically hear up to 15-17 kHz. If you still hear a buzz past that, it's your sound card or speaker distortion, not the signal — and not a broken speaker.
Do I need headphones?
Not required, but recommended: they separate channels unambiguously. On speakers, the phase test and the quiz lose precision because both channels mix in the room.
Related tools
Embed Speaker Test on your site
Add Speaker Test to any web page with a simple iframe. Free, with attribution to miguelacm.es.
<iframe
src="https://miguelacm.es/embed/speaker-test"
width="100%"
height="700"
frameborder="0"
title="Speaker Test — miguelacm.es"
></iframe>