shush

shush とは？

Every noise app ignores your room — playing the same sound regardless of what's already in the air, forcing you to turn it up. That volume is costing you REM sleep. Shush analyzes your room's frequency signature and removes those tones from its output. Complete broadband spectrum at a fraction of the volume. No other app does this. Smart sleep timer. Tinnitus notch filter. Real-time synthesis. Never loops.