This sound features a thin pulse wave with a 30% duty cycle that sweeps exponentially in pitch from 110 Hz to 1760 Hz over 4 seconds, creating a rising siren effect. A vibrato LFO modulates the pitch with increasing speed from 6 Hz to 18 Hz, adding tension and urgency. The signal passes through a resonant band-pass filter following the fundamental frequency to emphasize harmonics while thinning the lows, then undergoes heavy tanh saturation for digital grit. The stereo image is animated by an auto-panner speeding up from 1 Hz to 10 Hz, producing a disorienting spatial movement.
This effect suits electro and house genres, especially for builds and transitions around 120-130 BPM. It can be layered with heavier synths or drums to add tension but may need careful EQ to avoid clashing in the midrange. Use automation to blend it smoothly and avoid overpowering vocals or lead elements.