About the 256 Hz tone
256 Hz is a power of two, which made it a popular theoretical tuning for middle C in the past, sometimes called scientific pitch. In modern standard tuning (A4 = 440 Hz), middle C is 261.63 Hz, slightly higher.
A 256 Hz sine wave completes 256 cycles every second; each cycle lasts 3.906 ms, and the sound wave is about 134.0 cm long in air. The nearest musical note is C4.
Start with the volume low and raise it slowly. Use the slider to move away from 256 Hz, or try another preset: 20 Hz · 40 Hz · 50 Hz · 60 Hz · 100 Hz · 432 Hz · 440 Hz · 528 Hz · 1,000 Hz · 8,000 Hz · 15,000 Hz · 17,400 Hz · 20,000 Hz.
Questions
How do I play a 256 Hz tone?
Press Play above. The generator starts at exactly 256 Hz as a pure sine wave; you can change the wave shape and volume.
Why can't I hear 256 Hz?
Your speakers or headphones may not reproduce it, the volume may be too low, or it may be outside your hearing range. Very low and very high tones are the hardest.
Is it safe to listen to test tones?
At a comfortable volume, yes. Start quiet, and stop if anything feels uncomfortable.
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