What is brown noise?
Brown FM turns math into deep, continuous brown noise, generated live on your iPhone while you listen.
Illustration of the general frequency balance, not a measurement of Brown FM.
What is brown noise?
Brown noise is random sound weighted toward lower frequencies, giving it a deeper rumble than white noise. It can resemble heavy rain or distant water, though natural sounds have their own changing patterns. Compare brown, white, and pink noise to understand the difference in balance.
How is it made?
Your phone creates it live while you listen. The app rolls fresh random numbers thousands of times a second and smooths them into that deep rumble — the same way a synthesizer makes a tone.
Brown FM shapes those numbers through layered filters. Depth, Texture, Space, and Movement let you adjust the result.
Does it repeat?
Normal playback generates new samples continuously instead of restarting an audio file. For an example of that distinction, compare live-generated sound with a repeating recording.
A brown noise app for sleep and focus
Some listeners prefer a steady background while sleeping, studying, or working. Whether it makes a distraction less noticeable depends on the room, the sound, and the listener. Explore brown noise for sleep or focused work.
Save your sound and set a timer
Save your preferred sound settings and use a sleep timer with a gradual fade. Listening history and preferences stay on your device.
Brown FM requires iOS 26 or later and a subscription or lifetime purchase. See pricing and access or compare brown noise apps for iPhone.
A little less distraction.
Create a steady background for focused work or winding down.
Download Brown FM