Frequency Sweep Generator

Glide a tone across a frequency range and export it.

Everything runs in your browser. No audio is ever uploaded.

This sweep goes above 15 kHz. Keep the volume low: very high tones sound quiet but can still hurt your ears and stress a tweeter.

Start frequency (Hz)End frequency (Hz)Duration (seconds)

Sweep curve

Settings

Waveform

Volume-12 dB

Repeat the sweep

With repeat off the sweep runs once and stops. With it on it starts again from the beginning.

Download as WAV

The file is rendered in your browser over the duration you set, with the waveform and volume above. Nothing is downloaded from a server.

Set a low volume first, then raise it slowly. A good system stays even in loudness across the sweep; rattles, buzzes or sudden drops point at the speaker or the room.

Audio starts on your first tap on Play, as required by your browser. Press Space to start or stop.

A frequency sweep generator glides one tone across a range instead of holding it still. A sine sweep, also called a chirp or a glide tone, asks every frequency in turn whether your speaker, your room and your hearing still answer, so it finds problems a single test tone walks past.

How to use it

Set the range. Start and end frequency both accept anything from 20 Hz to 20 kHz, and a sweep that runs downward is as valid as one that runs up.
Choose the duration and the curve. Anything from 1 to 60 seconds works. A logarithmic sweep spends the same time in every octave, the way hearing is laid out; a linear sweep spends it in every hertz and races through the bass.
Pick a waveform and set the volume low. If your end frequency is above 15 kHz a warning appears, because those tones stress a tweeter and your ears while sounding quiet.
Turn on Repeat if you want the sweep to start again instead of stopping, which is what you want while you walk around a room or press on a panel to find a rattle.
Press Play or hit the space bar and watch the live readout to see which frequency is sounding at any moment. Download WAV renders the same sweep as a file over its own duration.

What you can use it for

Finding where a speaker gives up. Run 200 Hz down to 20 Hz at a moderate level and listen for the point where the tone thins out or disappears. That frequency is the real low end of the box, whatever the specification says.

Hunting rattles and resonances. Loop a slow sweep through the bass and walk around: a buzzing grille, a loose panel or a coin in a car door announces itself at one particular frequency and goes quiet again a moment later.

Checking room modes. Below about 200 Hz the room, not the speaker, decides what you hear. Move around during a slow sweep and you will find places where the level collapses and places where it doubles.

Testing your own high frequency hearing. Sweep 10 kHz to 20 kHz through wired headphones at a low level and note where it vanishes. Do it on the same hardware each time if you want to compare two dates.

Making a measurement file. A logarithmic sweep is the standard excitation signal for impulse response and frequency response measurement. Export it as a WAV and feed it into whichever measurement software you already use.

What to listen for, band by band

Band	What to listen for
20 to 40 Hz	Felt rather than heard. Only a subwoofer or a large driver reaches it; a laptop buzzes instead.
40 to 80 Hz	Kick drum and bass guitar weight. Loose panels, grilles and furniture usually start buzzing somewhere in here.
80 to 200 Hz	Male voice fundamentals and room modes. Big swings in level as the tone moves are the room, not the speaker.
200 Hz to 2 kHz	The core of speech and most instruments. It should glide by evenly; a dip here makes everything sound hollow.
2 to 6 kHz	Presence and consonants. Hearing is most sensitive here, so this band sounds louder even at identical power.
6 to 12 kHz	Cymbals and air. Most tweeters still deliver it; a tired or blown one starts to fade.
12 to 20 kHz	The top octave. Your age and your speaker both cut in here, and silence will not tell you which stopped first.

Accuracy and limits

A sweep you listen to is not a measurement. There is no reference microphone, the room contributes as much as the speaker, and your own hearing is far from flat. Use a sweep to find problems, and a measurement rig to put numbers on them.

Level is uncalibrated and high frequencies are the risk. A sweep that ends above 15 kHz carries real energy into a tweeter while sounding almost silent, so both the driver and your ears are easy to overdrive. Start quiet and raise slowly.

The readout estimates where the sweep has got to; it does not measure the output. The sweep is scheduled on the audio clock and stays accurate, but a Bluetooth link or an equalizer in the operating system still changes what leaves the speaker.

Frequently asked questions

What is a frequency sweep used for?

Covering a whole range in one pass. It finds the frequency where a speaker stops, the frequency where something rattles, and the frequency where your hearing ends, none of which you would find quickly by typing single tones.

Should I use a logarithmic or a linear sweep?

Logarithmic for almost everything, because it gives each octave the same time and matches how hearing works. Linear is useful when you want a fixed number of hertz per second, for example across a narrow high band.

Why does the sweep get louder in the middle?

Because your ears are not flat. Sensitivity peaks in the 2 kHz to 5 kHz region and falls off at both ends, so a sweep at constant electrical level sounds like a hump. Only a measurement microphone can settle what the speaker did.

Why do I hear a buzz at one frequency and not the others?

Something is resonating. A panel, a shelf or a loose object has a natural frequency and only rattles while the sweep passes through it. Loop the sweep and press on things one at a time until the buzz stops.

Can I download the sweep as a WAV?

Yes. Press Download WAV and the same sweep is rendered in your browser over the duration you set, with the current waveform and level. Nothing is fetched from a server.

Can a sweep damage my speakers?

At a sensible level, no. At a high level it can: a long stay in the top octaves heats a tweeter, and 20 Hz at full power moves a small driver further than it is built for. Keep the volume moderate and stop if the sound breaks up.