Free online frequency sweep generator. Glide a tone from 20Hz to 20kHz, or any range you pick, as a smooth log or linear sweep or in 1/3 octave steps. Hold any frequency, mark the spots where your speakers buzz, boom or drop out, and download the sweep as a WAV file.
The tone glides without a break from the start frequency to the end frequency. Use Log to give every octave the same time, which matches how ears hear pitch, or Linear to move evenly in hertz.
A frequency sweep is a single tone that slides from one pitch to another over a set time, most often from 20Hz to 20kHz, the range people can hear. Instead of playing hundreds of separate test tones, one sweep plays every frequency in between, one after the other.
Because the tone keeps the same level all the way through, any change you hear comes from your speakers, your headphones, your room or your ears. A loud spot means something is boosting that frequency, a quiet spot means something is cutting it, and the point where the sound vanishes is the edge of what your gear or your hearing can reach.
This sweep generator builds the tone live in your browser with the Web Audio API. Nothing is uploaded or recorded, and the plot on the screen shows exactly which frequency is playing at every moment.
A full range sweep takes 20 seconds. Follow the line from left to right.
Set your device to about 25%. The middle of the sweep sounds much louder than the ends, so start lower than you think.
Use Full Range for a general check, or a preset like Subwoofer or Treble to focus on one part.
Keep your ears on the level. Note where the sound gets louder, quieter, buzzy or silent.
Press Hold to stay on a problem spot, then Mark it so you can come back to that exact frequency.
Move the speaker, tighten a panel or change a setting, then run the same sweep to hear the change.
Both bars below run from 20Hz to 20kHz in the same number of seconds. Each block is one octave, where the frequency doubles. Watch how much of the time each octave gets.
Ten octaves, ten equal blocks. The bass gets as much time as the treble, which matches how we hear pitch. This is the sweep to use for most speaker, headphone and room checks.
The same distance in hertz every second. The first six octaves, from 20Hz to about 1.3kHz, rush past in the first 6% of the time, and the top octave takes half the sweep. It is handy for checking high frequencies in detail.
Each bar sits on the same 10Hz to 20kHz scale as the console. Press a button to sweep just that part in 10 seconds.
20Hz to 60HzThe rumble under films and electronic music. Small speakers drop out here first.
60Hz to 250HzKick drums, bass guitar and the punch in most music. Rooms cause the biggest bumps and dips here.
250Hz to 500HzWarmth and body. Too much here makes a mix sound muddy or boxy.
500Hz to 2kHzWhere most of a voice lives. Rattles in cheap enclosures often show up here too.
2kHz to 4kHzThe range ears are most sensitive to. This is where the sweep sounds loudest.
4kHz to 6kHzClarity and bite on vocals and guitars. Harsh speakers often peak here.
6kHz to 20kHzAir and sparkle. The top end fades first, both on cheap tweeters and with age.
A perfect speaker in a perfect room would sound even from start to end. Real ones never do, and each kind of change points to a different cause.
You have reached the limit of the speaker, the headphones or your own hearing.
A resonance is boosting that note. In the bass it is usually the room, higher up it is often the speaker box.
Sound waves are cancelling out at your seat, or a crossover between drivers is not blending well.
A loose part is shaking at that frequency. It is rarely the speaker cone itself.
The speaker or amplifier is distorting, often because the volume is too high for that frequency.
The two speakers or earcups do not match, or one is placed differently in the room.
Use these as landmarks while the sweep plays. Press any row to hold that exact frequency as a steady tone.
| Frequency | Range | Where You Hear It | Hold It |
|---|---|---|---|
| 20Hz | Sub Bass | The bottom of human hearing and the deepest film rumble. | |
| 41Hz | Sub Bass | The open low E string on a bass guitar. | |
| 50Hz / 60Hz | Bass | Mains hum. 50Hz in Europe and most of Asia, 60Hz in North America. | |
| 100Hz | Bass | The thump of a kick drum and the low end of a deep voice. | |
| 261.6Hz | Low Mids | Middle C on a piano. | |
| 440Hz | Midrange | A4, the note most instruments tune to. | |
| 1kHz | Midrange | The standard audio test tone for levels and cables. | |
| 3kHz | Upper Mids | Close to where ears are most sensitive. A baby's cry sits around here. | |
| 6kHz | Brilliance | The hiss of an s sound and the shimmer of cymbals. | |
| 10kHz | Brilliance | Air on vocals and the top of most cymbal sounds. | |
| 15kHz | Brilliance | Many adults stop hearing somewhere around here. | |
| 20kHz | Brilliance | The top of hearing for young ears. Most speakers stop near here. |
Start quiet before playing the 3kHz to 20kHz rows. High tones can sound faint and still be loud.
One sweep answers a lot of questions about sound. These are the jobs it does best, each with a sweep ready to play.
Hear the whole range in 20 seconds and check for dead spots, harsh peaks or buzzing before the return window closes.
Find out how deep and how high your headphones go, and use the Left and Right buttons to compare each side.
A slow bass sweep shows the notes your room boosts and the ones it swallows. Move the speaker or your seat to smooth it out.
Let the sweep run up and down while you press on door cards and trim. Mark each buzz to come back to it.
Note where the high tone fades away for you. The limit often drops with age. Use the Hearing Test for a full check.
Show students how pitch rises, how octaves double and how a room changes sound, with the plot on screen to follow.
More than a tone that slides up. Every part of the sweep is yours to set.
Glide without a break, or jump through standard 1/3 octave steps from 10Hz to 20kHz. Choose a log curve to give every octave equal time, or linear for even hertz, then play once, loop or go up and down.
Hear something odd? Press Hold to freeze the sweep on that exact frequency as a steady tone, then Resume to carry on from the same spot.
See the path, the played part and the waveform.
Tap the scale to skip straight to any frequency.
Save problem frequencies and replay them in one tap.
Sweep one speaker or earcup at a time.
Full range, sub, bass, mids, treble and more.
Copy a link that opens your exact sweep settings.
Save one full pass, or up to 2 minutes of a looped sweep, as a 44.1kHz stereo WAV for a media player, a car stereo or audio software.
The sweep is made on your device. There is no upload, no microphone and no account.
It is free, exact and works with the speakers and headphones you already own.
Sweep any part of the full hearing range and a little below it.
Standard step points for checking a speaker one band at a time.
Runs in Chrome, Edge, Safari and Firefox on phone or computer.
Take a clean sweep offline in a single file.
A frequency sweep is safe at normal listening levels. Because ears hear the middle of the range far louder than the ends, these habits matter more here than with music.
Hold 1kHz first and set a comfortable volume there. Do not turn up to hear the bass or the top end better.
Tones above 8kHz can be hard to hear and easy to play too loud. Stop if your ears ring or feel full.
Loud deep bass can damage small speakers, and dogs and cats hear high tones that people cannot.
Plain answers about sweeps, curves, ranges and what you hear.
A frequency sweep is a test tone that slides from one frequency to another over a set time, usually from 20Hz to 20kHz. It plays every frequency in that range one after another, so you can hear how speakers, headphones, a room or your ears respond across the whole range.
A log sweep gives every octave the same amount of time, so the bass and the treble get equal attention, which matches how we hear pitch. A linear sweep moves the same number of hertz every second, so the low end rushes past and the top octave takes half the sweep.
Set a low volume, choose Full Range and press play. Listen for spots where the sound gets louder, quieter, buzzy or silent. Press Hold to stay on a problem frequency, mark it, then fix the cause and sweep again.
20Hz to 20kHz covers the full range of human hearing and is the best general check. Use 10Hz to 200Hz for a subwoofer, 20Hz to 300Hz for room bass problems, and 8kHz to 20kHz to check tweeters or your upper hearing.
20 seconds is a good length for a full range sweep. Use 30 to 60 seconds when you are hunting rattles or room problems, so you have time to notice each change, and 5 seconds for a quick check.
Either your speakers or headphones cannot play that frequency, or it is past the limit of your hearing. Phone and laptop speakers drop out early in the bass, and many adults stop hearing somewhere between 14kHz and 17kHz.
In the bass it is usually your room, which boosts some frequencies and cancels others depending on where you sit. Higher up it can be the speaker itself, its box or the way its drivers blend. Moving the speaker or your seat often changes the result.
A stepped sweep jumps through fixed frequencies instead of gliding. This tool uses the standard 1/3 octave points, such as 31.5Hz, 63Hz, 125Hz and 1kHz, and holds each one for the time you choose so you can judge every band on its own.
It can show the highest and lowest tones you hear on your current speakers or headphones, which is a useful rough check. It is not a medical hearing test. See an audiologist if you notice changes in your hearing.
Yes. Set up your sweep and press Download WAV. A single sweep saves one full pass, and a looped sweep saves 30, 60 or 120 seconds. The file is a 44.1kHz, 16-bit stereo WAV.
Yes, at a sensible volume. Set the level on a 1kHz tone, keep it there for the whole sweep, keep high sweeps short and stop if you hear distortion or your ears feel uncomfortable.
Yes. It runs in any current browser on iPhone, iPad, Android, Windows, Mac and Chromebook. On iPhone, turn off silent mode or use headphones if you hear nothing.
Test speakers, headphones, your microphone and your hearing, all free and all in your browser.
Real problems from listeners, answered and checked by the Sound Tester Audio Team.
No discussions about this tool yet. Start the first one and the team will answer it for free.