Deep brown noise
Brown noise with everything above about 200 Hz filtered away. Felt as much as heard.
Timer
Generated in your browser with the same code as the app, nothing to download. Start with your volume low. Keep this tab open.
About this sound
Deep brown noise is brown noise taken one step further. What is left is a soft, low hum with no hiss at all, something like the rumble inside a ship or a big building's ventilation heard from another room.
It is generated the same way as brown noise (a random walk with a small leak back toward zero) and then sent through a low-pass filter at 200 Hz. Everything is computed live in your browser with the app's code, from a 30-second buffer with a crossfaded seam, and the level is trimmed so it plays as loud as the other sounds.
How people use it
People who find even brown noise too bright often settle on this. It is good at covering low, booming sounds and leaves the room feeling quiet rather than full. On small phone speakers much of it can disappear, so a speaker with some bass or headphones carries it better.
Keep the volume moderate: low frequencies feel quieter than they are. It also works as a floor under other sounds, for example rain or the airplane cabin, to add weight without adding hiss.
Questions
Why can't I hear deep brown noise on my phone?
Small phone speakers reproduce very little below a few hundred hertz, which is exactly where this noise lives. Try headphones or a speaker with more bass.
Is deep brown noise the same as red noise?
Red noise is another name for brown noise. Deep brown is brown noise with an extra low-pass filter at 200 Hz, so it is darker than ordinary brown or red noise.
Mix it with
Get deep brown on your phone
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