Yelp Siren

How it's made

Source

an electronic emergency siren drives a compression speaker continuously at 650–1550 Hz. Phase-coherent sine partials at 1, 2, 3 and 5 times the swept fundamental model its driven diaphragm.

Body

the third harmonic supplies the penetrating edge; a weaker second adds speaker asymmetry. A broad 2.3 kHz horn emphasis (Q 0.65, +2 dB), 280 Hz high-pass and 6.4 kHz low-pass shape the output.

Envelope

no silent gaps; level breathes from 84 to 100 percent with each sweep. Rounded cosine ramps spend 60 percent of each cycle rising and 40 percent falling, with zero slope at both turns.

Modulation

12 sweeps in the four-second default loop (3 Hz); every preset uses whole sweep cycles. Harmonic brightness grows on the rising pitch, as a horn becomes more efficient in its upper band.

Variation

sweep count, lower pitch, span and harmonic edge control the siren's mechanism. Presets cover standard yelp, urgent rapid yelp, a lower broad sweep and a compact high-register alarm.

Space

dry and mono for placement; no room tail, hiss bed, transient or unrelated machine drone.

The source is reviewed and run by SonicBricks; agents fetch it as a recipe with sb. It is not published on this page.