White Noise
Constant power across all frequencies. Ideal for masking distracting speech.
FREQUENCY: HIGH
Red Noise
Brown noise taken further down — heavier, darker, almost tactile.
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Sound Library
Calibrated frequencies for deep work and relaxation.
Color Noises
Continuous frequencies for auditory masking.
Brown Noise
Deep, bass-heavy rumble reminiscent of a distant waterfall or thunder.
FREQUENCY: LOW
Pink Noise
Balanced spectrum that sounds more natural to the human ear, like steady rain.
FREQUENCY: BALANCED
Red Noise
Even deeper than Brown noise, focusing heavily on the low-end spectrum.
FREQUENCY: LOW
Black Noise
Near-silence with subtle low-frequency drift. Meditative, like the sound of a quiet room at night.
FREQUENCY: NEAR SILENT
Grey Noise
Psychoacoustically equalized to sound equally loud at every frequency.
FREQUENCY: EQUALIZED
Ambient Sounds
Natural soundscapes recorded in high fidelity.
Rain
Gentle rainfall creating a natural, soothing atmosphere perfect for deep concentration.
SOURCE: RECORDED
Rain on Tent
Rainfall on a tent canvas — cozy, immersive and deeply relaxing for focused work.
SOURCE: RECORDED
Ocean Waves
Rhythmic ocean waves rolling onto shore — a timeless natural soundscape for calm focus.
SOURCE: RECORDED
Wind
Steady breeze flowing through open spaces — airy and expansive for clear thinking.
SOURCE: RECORDED
Forest Stream
A gentle brook flowing through a quiet forest — peaceful and grounding for deep work.
SOURCE: RECORDED
Meadow
Birds and insects in a sunlit meadow — warm, organic ambience for relaxed focus.
SOURCE: RECORDED
Binaural Beats
Brainwave entrainment through stereo frequency offset. Layers with any noise above.
Headphones required for binaural effect
Delta
Deep sleep and healing. Ultra-low 2 Hz beat for total relaxation.
BEAT: 2 Hz
Theta
Meditation and creativity. 6 Hz beat for deep introspection and flow.
BEAT: 6 Hz
Alpha
Calm focus and learning. 10 Hz beat for relaxed concentration.
BEAT: 10 Hz
Beta
Active thinking and energy. 14 Hz beat for alertness and problem solving.
BEAT: 14 Hz
Red and brown: the same family
In strict signal processing, "red noise" and "brown noise" name the same 1/f² spectrum, and you will find both terms used interchangeably in textbooks. In practice, listeners use them to describe different things, and the sound libraries that people actually use have followed suit.
On FocusNoise, red noise is the darker of the pair: the same random-walk generation as brown noise, but with a longer smoothing constant that pushes even more of the remaining energy below the range where you hear pitch. Where brown noise still reads as a rumble, red noise reads closer to pressure.
What it is like to work in
Red noise is the setting to try when brown noise is nearly right but still feels present. Because so little of its energy reaches the frequencies your ear emphasises, you can run it fairly loud before it registers as a sound in the room at all. That makes it effective against low-frequency intrusions that brighter noise leaves untouched — traffic through a window, a plant room, a neighbour’s bass.
It is a poor choice against voices. Speech intelligibility depends on high frequencies, and red noise has almost none, so a conversation nearby will cut straight through it. If chatter is your problem, layer red noise underneath white or pink rather than using it alone.
Playback notes
Deep material is where playback equipment matters most. Laptop speakers and small earbuds roll off the bottom of the spectrum, which can leave red noise sounding like nothing at all — the energy is there, the drivers simply cannot move it. Over-ear headphones or a speaker with real low-end response will show you what it actually sounds like.
If red noise turns out to be too much of nothing, black noise takes the idea one step further into near-silence, and brown noise sits one step back towards audible.
Common questions
Are red noise and brown noise the same thing?
Technically yes — both describe a 1/f² spectrum. Here they are two separate presets: brown is the standard rumble, red is generated with heavier smoothing so it sits noticeably deeper. Play both back to back and pick whichever suits the room.
I can barely hear it. Is it working?
Probably, but your speakers may not be reproducing it. Red noise concentrates its energy at the bottom of the spectrum, which small laptop and phone speakers cannot reproduce. Try headphones before adjusting the volume upward.
Will it mask people talking?
Not well on its own. Voices carry in the mid and high frequencies that red noise deliberately lacks. Add a layer of white or pink noise on top — both can play simultaneously with independent volume.