How to use the tone generator
- Set the volume low, choose a frequency with the slider or a preset and press Play.
- Change the waveform or play through only the left or right speaker.
- Press Sweep to glide from 20 Hz to 20 kHz and note where you stop hearing the tone.
What the waveforms sound like
A sine wave is a single pure frequency, ideal for hearing tests and tuning. Square waves sound hollow and buzzy, sawtooth waves bright and harsh, and triangle waves soft and flute-like, because each adds a different mix of harmonics.
Practical uses
Find rattles in a car or room with a slow bass sweep, check that headphones and subwoofers reproduce low frequencies, tune instruments to 440 Hz, test left and right channels, or mask tinnitus with a matching tone (ask a doctor first).
Hearing test caveats
An online sweep shows roughly where your hearing stops, but speakers, headphones and volume settings limit the result. For a real hearing test, see an audiologist.
Frequently asked questions
What frequencies can humans hear?
About 20 Hz to 20 kHz when young. The upper limit drops with age; many adults stop hearing around 14β16 kHz.
How do I test left and right speakers?
Choose Left or Right under Speaker. The tone should come only from that side; if not, the channels are swapped.
Why can't I hear very low tones?
Small laptop and phone speakers can't reproduce bass below about 100β200 Hz. Use headphones or larger speakers.
What is the difference between waveforms?
A sine wave is a pure tone. Square, sawtooth and triangle waves add harmonics and sound buzzier.