Sleep session · I20
Ninety Minute Still
A staged journey: 12 Hz → 6 Hz → 2 Hz → 0.8 Hz, over 60 minutes.
Choose the full transition or begin at the advertised audio target. You can scrub and extend either path in the player.
Frequency journey
How the rhythmic pulse embedded in the sound changes from the opening moments to its destination.
The embedded pulse moves through 12 Hz → 6 Hz → 2 Hz → 0.8 Hz, creating distinct phases instead of one straight ramp. The authored target begins at 60 min and holds for 15 min.
Wind-down and sleep preparation
For a sleep routine, the sound is designed to become easier to leave in the background as the session develops.
Give the transition room
Bedtime routines, quiet rest, and moving away from active listening. Start quietly and let the ramp unfold instead of judging the session in its first minute. The target then holds for 15 min by design. You can also start directly at the target, scrub the journey, or extend the hold in the player.
Signal, not a scan. The line shows the modulation rate generated in the audio. It is not an EEG reading and does not promise that brain activity will follow the curve. Listening responses vary.
Signal specification
Every audible behavior is published. The values below describe the sound engine—not a biological dose or guaranteed effect.
Journey
- Beat start
- 12 Hz Alpha
- Beat target
- 0.8 Hz Delta
- Ramp
- 60 min
- Session length
- 75 minutes
Sound field
- Carrier
- 168 Hz
- Modulation
- Isochronic
- Modulation depth
- 0.97
- Envelope
- Smooth bell
- Duty cycle
- 50% on
- Noise field
- Sub Brownian
- Spatial orbit
- 0.018 Hz one turn every 56s
Playback
- Delivery
- Isochronic, Monaural, Binaural or Poly-rhythmic
- Listening setup
- Speakers or headphones
Choose the spatial feel
This session starts in isochronic mode. You can change how the beat is delivered without changing the frequency journey, or add a Shepard-Risset carrier drift for a continuously falling timbre.
- Monaural
- Two tones summed before they reach you, so the beat exists in the air rather than being built in your head. Smoother and less percussive than isochronic, and it works on speakers.
- Binaural— needs stereo headphones
- Two carriers a few hertz apart, one per ear. The beat is constructed in your brainstem, so it needs stereo headphones to exist at all.
- Poly-rhythmic— needs stereo headphones
- Each ear gets its own carrier and its own beat, related by the golden ratio rather than driven in lockstep. Needs headphones — on a speaker the two channels sum and the distinction is lost.
New to these terms? Every row above, explained in plain language.
How this one is built
Full ultradian length, sixty to ninety-five minutes, on multi-waypoint curves rather than a single slope. The beat descends in stages with waypoints in between, so the trajectory follows the shape of a sleep cycle instead of a straight line to delta.
Listen responsibly
Brainwavest is a wellness and relaxation tool, not a medical device. Session names and guidance describe design intent, not a promised physiological result. Binaural mode requires stereo headphones. Start quietly, and never use rhythmic audio while driving. Read the full safety notes.