Generate pure tones, noise (white/pink/brown), frequency sweeps and speaker tests (channels and polarity). To test speakers and subwoofers, calibrate a room or tune by ear.
A free online tone & noise generator: play pure tones at any frequency (sine, square, triangle, sawtooth), white, pink or brown noise, frequency sweeps and speaker tests. Everything is generated in your browser — nothing to install.
What it is for
Test if a speaker reaches a frequency, set levels with pink noise, or tune by ear. The sweep glides through a band — subwoofer, bass (woofer), mids, treble (tweeter) or the full range — so you can hear how far each driver reaches and find rattles or room resonances. The speaker test checks left/right channels and speaker polarity (phase) to catch a swapped + / − wire. Use headphones for channel tests and keep the volume sensible.
Frequently asked questions
What is pink noise used for?
Pink noise has equal energy per octave, which matches how we hear, so it is the standard signal to set speaker levels, calibrate a room with an RTA, or test subwoofers. White noise sounds brighter (equal energy per Hz); brown noise is deeper and softer.
What can I do with the tone generator?
Test whether a speaker or headphone reproduces a given frequency, check left/right channels, find rattles and resonances, tune instruments by ear, or match a tinnitus tone. Pick the waveform and channel you need.
How do I test a speaker with the sweep?
Pick a band that matches the driver — subwoofer, bass (woofer), mids, treble (tweeter) or full range — and play the sweep. It glides through the range so you can hear how low or high the speaker reaches, spot dropouts or distortion, and find room resonances or panels and furniture that rattle. Choose a one-shot, a loop or a back-and-forth sweep.
What is the polarity (phase) test for?
It plays noise on both channels and lets you flip one channel’s polarity. With speakers wired correctly, “in phase” sounds centered and full while “out of phase” sounds diffuse and thin. If you hear the opposite, one speaker has its + and − wires swapped — re-check the connections.
What is the rhythm track for, and is it copyright-free?
The Beat tab plays a rhythm track (drums and bass) synthesized live in your browser with oscillators and noise — there is no recording involved, so it is royalty-free by construction. It lets you audition speakers with music-like material: kick and bass in the lows, snare in the mids and hi-hats in the highs, at the tempo you choose.
Is it safe?
At a sensible volume, yes. Start low and raise slowly: pure tones — especially high frequencies and square waves — can be harsh and, if very loud and prolonged, harmful. Use it responsibly, ideally with headphones for channel tests.