The 25 Hz frequency is categorized under Test Tones. It is known for: A very low bass frequency, ideal for evaluating subwoofer extension and rumble. Also: High-beta state, associated with complex thought and active concentration..

Our free online tone generator allows you to play this 25 Hz frequency instantly. Use the controls above to adjust the volume or switch waveforms (sine, square, sawtooth, triangle) to hear the different timbres.