Common Active Noise Cancellation Applications Noise Cancellation in Automobiles Noise Cancelling Headphones

What about HVAC applications? Can Active Noise Cancellation techniques be applied to HVAC applications? Noise can come from multiple locations

ANC Concepts Feed-forward ANC Feed-back ANC Hybrid ANC Through research - can determine which concept is the most effective & easiest to develop for this application Hybrid ANC Feed-back ANC with residual error microphone

Applications – where & why is this needed? Hotel ‘Ptech’ units Classroom units Exterior equipment Building retrofit - more efficient equipment into existing space Hotel unit – I never get a good night sleep because I am either disrupted by Ptech noise or if I turn unit off – I am too hot/cold. Anniversary trip when hallway ahu had radiated noise through the wall & we couldn’t sleep + elevator noise. Classroom – Lakin project w/ UVs in each room. We maintained acceptable ASHRAE noise criteria but students sitting close to the unit still experience a disturbingly high level of noise (effects learning & requires teachers to speak louder for those students) Exterior – anyone ever experienced a noisy air conditioner? Mechanical / boier rooms – equipment designers are getting much better at reducing noise but often these rooms are so loud you can’t even hold a conversation Retrofits – often updating to more modern HVAC systems requires obtaining equipment that doesn’t fit neatly into existing building architecture, so noise generating equipment often needs to be installed near occupied areas & higher occupant noise levels are experienced at the benefit of energy savings. Mechanical / Boiler Rooms

Goals min. 10dB noise reduction from 20 Hz to 20 kHz easy to set up / calibrate (if necessary) ‘Function over Form’ Prototype - no size restriction Battery powered or 120 VAC powered