Walls don't stop it. Barriers don't bend it. Distance barely dulls it. Phase LF cancels low-frequency noise at the source — with clamp-on active noise control that installs in minutes on the equipment you already run.
Below 250 Hz, sound stops behaving. Wavelengths stretch to meters, passive absorbers become uselessly thin, and barriers are simply diffracted around. The low hum from fans, generators, and industrial machinery carries for kilometers, passes through walls, and drives the complaints, ordinances, and permitting fights that stall projects. The industry's answer has been mass and distance. Neither scales.
The Phase LF duct unit clamps onto the discharge of the fans you already operate. A contactless blade-pass sensor and an error microphone feed a self-tuning DSP that drives an anti-phase speaker inside an open duct section — cancelling the fan's low-frequency tone in the air, with zero impact on airflow and no modification to the fan itself.
| Control band | 40 – 250 Hz |
| LF cancellation | Up to 15 dB |
| Adaptive algorithm | FxLMS, self-tuning |
| Convergence time | < 60 s after power-on |
| Fan compatibility | Axial, 25 – 49 in diameter |
| Airflow impact | Negligible — open duct section |
| Equipment modification | None |
| Supply | 100 – 240 VAC, < 50 W |
| Enclosure | Outdoor, weather-resistant, −20 to +55 °C |
| Unit weight | 40 lbs |
A bench demonstration of the Phase LF unit on a running fan. The controller powers on, converges on the fan tone, and pulls the low-frequency hum out of the air in real time — no enclosure, no shutdown, no tuning.
What you hear in the video is what a fence-line neighbor hears: the tone drops, the airflow stays.
One standardized unit. Any common large fan or rotating machine. No custom engineering — and before/after dB spectra provided with every installation.
Data center dry coolers, CRAC units, and chiller fans — the blade-pass hum that defines a facility's fence-line noise.
Standby and prime power gensets whose firing-frequency drone carries far beyond the pad.
Process fans, blowers, and rotating machinery on plant floors and rooftops.
Commercial rooftop units and chiller plants operating next to offices, hospitals, and homes.
Large air-source heat pump installations facing residential low-frequency noise limits.
Continuous-duty compressor and pump stations with persistent tonal noise.
Tell us about your site and the equipment you run. We'll tell you what Phase LF can take off your spectrum — with measured before/after data from every installation.
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