Deep sleep music for the nights regular sleep sounds do not reach
Regular sleep music is built to be quiet. Deep Sleep mode is built to be low. Seven detuned drone voices instead of Sleep's five, a twelve-second reverb tail instead of nine, and a filter that never opens past 460Hz, so almost nothing in the mix sits above the range a room's own hum already occupies. There is a real acoustic reason low and steady works better than quiet alone. It is the same auditory masking principle hospitals and sleep researchers rely on when they test constant background noise against ward or traffic sound: a steady low bed raises the level a sudden noise has to reach before it registers as a change worth waking up for. Deep Sleep exists for the nights an ordinary sleep preset still feels like it is happening a little too close to the surface.
Bells that arrive once a minute, if at all
Sleep mode's chimes land every fifty-five to a hundred and thirty seconds. Deep Sleep stretches that to ninety-five and a hundred and eighty, and cuts the chance of one firing at all to roughly one in twelve. The intent is not to remove melody entirely, just to make it rare enough that it never becomes something to wait for. Most of what carries the mode is the drone and whatever texture sits under it.
Built for stereo width you feel more than hear
Stereo width is set to its widest anywhere in StillTune here, wider than Sleep, Relax or Focus. Combined with the long reverb tail, a low-frequency source stops reading as coming from one direction and starts reading as filling the room instead, which is closer to how an actual building's ambient hum behaves than a point-source sound ever does.
Choose what you are sinking into
Every mode runs from a Sound DNA recipe you can adjust while it plays:
- Brown noise on its own. The default: dense, low, and enough by itself for most nights.
- Slow ocean waves. Swap in waves at a long swell period, fourteen seconds or more between crests, for something that arrives rather than repeats.
- An enclosed, cave-like space. Layer in the cave texture for an occasional distant drip under the same low drone.
- Rain further away. Thin rain density down and let the drone dominate, closer to rain on a roof several floors up than against a window.
Save the mix once it is right, or start from one already tuned: the Deep Sleep sounds library has published recipes, most of them variations on exactly these ideas.
No download, no seam, hours on nothing
StillTune stores the score rather than an audio file, so a Deep Sleep session keeps generating for as long as it runs instead of looping back to a seam that could wake you. Load it once while connected, then Airplane Mode handles the rest of the night.
Try it before reading further
Press play below. If it turns out to be heavier than you actually need, regular sleep music is one step lighter on the same engine. No account is needed to listen.