Test speakers, headphones, and audio systems with a free online tone generator supporting frequencies from 20 Hz to 20 kHz. Choose sine, square, sawtooth, or triangle waveforms and play sound through both ears, the left channel, or the right channel. Preset frequencies and a 20 Hz to 20 kHz sweep make quick audio checks simple and convenient. https://aitoolspros.com/tools/audio/tone-generator/