Metronome

two metronomes · beat tones · noise · drift-free timing

Binaural beat

200
Quick band
7.0
Theta
Two tones, one per ear, a beat-rate apart. The beat exists only in your head, so this one needs headphones. Swap flips which ear gets the higher tone.

Monaural beat

200
Quick band
7.0
Theta
Both tones summed into one centered signal, so the beating is physically in the sound. Works on any speakers or headphones. No ear-swap (it's centered).

Isochronic tone

200
Quick band
10.0
Alpha
A single tone switched on and off at the pulse rate. Works on any output. Pulse depth sets how far the tone dips between pulses (100% = full silence, lower = a gentle throb).

Pure tone (drone)

200
A steady sine tone, no beat. A plain drone layer to sit under anything else.

Noise

Color
The three buttons are true noise colors: brown is deep and rumbly (like heavy rain or a waterfall), pink is balanced and natural (like steady rainfall), white is bright full-spectrum hiss. The fine-tune slider then shapes the brightness from there. Runs continuously, independent of the metronomes.

Cheatsheet (the lore)

Brainwave bands
BandRateWhat it's "for" (lore)
Delta0.5–4 HzDeep dreamless sleep, physical recovery. Used for sleep onset and deep rest.
Theta4–8 HzDrowsy, meditative, hypnagogic. Used for meditation, creativity, deep relaxation.
Alpha8–12 HzCalm but awake, "relaxed alert." Used for relaxation, light focus, stress relief.
Beta13–30 HzActive, engaged, problem-solving. Used for focus, alertness, concentration.
Gamma30 Hz+Peak concentration, high-level processing. Used for sharp focus, "flow."
Noise colors
ColorCharacterWhat it's "for" (lore)
BrownDeep, rumbly, bass-heavyMasking low rumble, grounding, sleep. Like a waterfall or heavy rain.
PinkBalanced, naturalFocus and sleep; the most "natural" sounding. Like steady rainfall or wind.
WhiteBright, full hissMasking sudden sounds, blocking distractions. Like static or a fan.
Tone delivery
TypeNeedsWhat it's "for" (lore)
BinauralHeadphonesThe classic. Subtle; the beat is built by your brain from the two ears.
MonauralAnythingStronger, more present beat. Works on speakers; good when headphones aren't an option.
IsochronicAnythingThe most overt pulse. Often described as the most "engaging" for focus.
Honest caveat: this is the popular/traditional lore, the framing the communities around these tools use. The audio phenomena are real, but the claimed mental effects (focus, sleep, relaxation) have mixed and modest scientific support. Treat the "what it's for" column as folklore to explore, not medical fact. The bonus is the bonus; the distraction is the point.

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