Bass that calms — the biometric coaching loop

Sub-bass and stress hormones have a documented relationship. Vibe's sleep routine taps into it. Here's the science, and the feature.

The counterintuitive thing about bass

Most people associate bass with intensity — the drop, the kick, the physical sensation of a speaker moving air. But controlled sub-bass exposure has a measurable calming effect. The research goes back to the 1990s and has been replicated consistently.

The mechanism is vibroacoustic: low-frequency sound activates the vestibular system, which overlaps with the parasympathetic nervous system. Certain bass frequencies trigger the same physiological response as deep breathing.

What 'goodnight' actually does

Vibe has a voice command called 'goodnight.' Say it and the app starts a sequence: volume ramps down over 12 minutes, the EQ shifts to a low-shelf tilt, a sleep timer fires.

It's not magic. It's a well-sequenced wind-down. But the EQ shift is deliberate — tuned specifically around the frequency ranges associated with lower cortisol in the vibroacoustic literature.

The beta loop

What we're building next goes further. The biometric coaching loop uses heart rate data — via Bluetooth from a wearable, or the phone's sensor — to dynamically adjust the EQ tilt as you fall asleep. If your heart rate isn't dropping, the bass gets softer. If it is, it holds.

"I stopped needing sleep sounds. The EQ does the same job but it's music I actually like."

— beta tester, Amsterdam

The limit

We're not making medical claims. This is audio design informed by psychoacoustics research, not a therapy product. But the gap between 'this sounds good' and 'this makes you feel better' is smaller than most audio companies admit.