Active noise cancellation (ANC) works on the interference principle: a microphone captures unwanted noise, a processor generates an anti-phase signal, and a speaker emits 'anti-sound' that neutralises the original noise. In headphones this technology is standard. Now ANC scales to architectural spaces: waiting areas, reception desks and conversation corners in lobbies. Noise reduction: up to 15–20 dB in the 50–500 Hz range. Adoption in commercial interiors has grown rapidly since 2024, with proven ROI in healthcare, hospitality and premium office segments.
How Spatial ANC Works
A microphone array (4–16 units per zone) captures the sound field structure. A DSP processor calculates the anti-phase signal for each of 4–8 broadband speakers within 2–5 ms. A 'quiet zone' of 1.5×1.5 to 3×3 metres is created, inside which low-frequency noise (HVAC, traffic, lifts) drops by 12–20 dB.
Technology limitation: ANC is most effective below 500 Hz. For mid and high frequencies (speech, phone calls) it is combined with passive sound-absorbing panels NRC 0.80+ and masking systems.
Equipment and Placement
An ANC module comprises: processing — DSP board with ≤5 ms latency; microphones — MEMS array with −26 dB FS sensitivity; speakers — coaxial 4–6" covering 40–800 Hz. Modules install in suspended ceilings or integrate into furniture (chair backs, partitions).
For a 3×3 m waiting zone, one ceiling module (4 microphones + 4 speakers) suffices. For the reception desk — 2 modules aimed at the administrator and visitor positions. Power: 15–30 W per zone. Control: RS-485, Ethernet.
Pricing and Effectiveness
One ANC module (3×3 m zone): from $3,200 (including DSP, microphones and speakers). Turnkey solution for a 100 m² lobby (3–5 quiet zones + passive acoustics): from $14,000. Installation: 2–4 working days. Calibration: 4 hours per zone.
Effectiveness is verified by measurement: in the ANC zone noise drops from 62 dB to 44–48 dB. That is the difference between a busy office and a quiet library. ROI for medical clinics (reduced patient stress, raised NPS): 12–18 months.