What kind of headphones should I use to listen to the iAwake audio files?
For optimal results, we recommend that iAwake products be used with stereo headphones that have a frequency response of 20 – 20,000 Hz.
Headphones are best, but if you want to use earbuds, make sure they are high quality (the same goes with headphones too!)
Go here to see specific recommendations.
You do not need headphones that go down to .01 Hz (for example) because it is the brain rhythm that is reached (using higher frequencies) not the pitch of the carrier tone that is delivering the brain rhythm. So, again, headphones that have a frequency response of 20 – 20,000 Hz – which is typical – are fine.