How to use Tone Generator
- Turn your volume down a little, then tap Play.
- Drag the slider or type an exact frequency in hertz. Use the −1/+1 and −10/+10 buttons for fine changes.
- Switch between sine, square, sawtooth and triangle to hear how each wave sounds.
Uses for a tone generator
A steady tone is handy for tuning instruments (440 Hz is the A above middle C), finding rattles in a car or room, testing a subwoofer's lowest note, or checking where your hearing or speakers cut off.
Sine waves are the purest sound, with a single frequency. Square and sawtooth waves add harmonics, so they sound buzzier and are easier to hear on small speakers. The slider is logarithmic, so every octave gets the same amount of space.
Frequently asked questions
What frequency is the musical note A?
Concert A is 440 Hz. Each octave doubles the frequency, so the A above it is 880 Hz and the one below is 220 Hz.
Can I change the frequency while it plays?
Yes. The tone glides smoothly to the new frequency without clicks.
Why can't I hear very high or very low tones?
Most speakers can't play below about 50 Hz, and many adults can't hear above 15 to 17 kHz. Headphones usually cover a wider range.