What is a Noise Cancelling Handset and How Does It Work?
Noise Cancelling Handsets are handsets designed to help cancel out background noise and prevent it from being transmitted through the handset. By adding a second sound port to the handset, the microphone is able to effectively differentiate background noise from the person speaking into the handset.
Cancelling out the background noise from the handset helps in two ways. First, the person on the other end of the line will be able to hear the speaker more clearly with the background noise removed. Second, it makes it easier for the person using the handset to hear by removing the background noise from the sidetone. Noise cancelling handsets can also be helpful in eliminating paging feedback loops when there's a paging system near the phone.
Noise Cancelling Handsets Are Great For:
- Factory floors with ambient equipment noise
- Restaurant take-out phones in a busy/noisy area
- Eliminating paging feedback on phones near paging speakers
- Offices or cubicles that are very close together
- Call Centers (it's very unprofessional when you can hear the other operators in the background!)
- Sensitive environments such as trading desks or legal offices NOTE: If you're REALLY serious about security, a push-to-talk (PTT) handset is the better way to go.
We Make Noise Cancelling Handsets for Hundreds of Types of Phones
Give us a call at 630-980-7710 to see if we can make yours!
How Does a Noise Cancelling Handset Work?

Noise Cancelling Handsets are used in areas with lots of background noise like factories or restaurants, or in areas where when you page from a phone you hear feedback - because that phone is near a paging horn or speaker.
The Noise Cancelling Transmitter is a very unique and sophisticated device. That type of microphone has openings in both the front (like all mics), as well as the back.
Since ambient noise enters the mic from both the front and rear, the same pressure is on both the front and rear of the diaphragm. Because the ambient noise doesn't make the diaphragm vibrate, the ambient noise isn't heard.
Since speech is entering from just the front of the mic, the diaphragm vibrates from just the speech... Cancelling out the noise.
With a noise cancelling handset (or headset), you must speak directly into the mic - you can't hold it under your chin and expect to be heard by the other party.

On the left is a Noise Cancelling mic in a typical handset with the port to the rear of the mic, and the volume control (POT) to lower the mic level for the particular environment.
Some handsets don't have enough room near the transmitter to fit a second sound port. If it's not possible to make a noise cancelling handset for your phone, we have an Electret Mic Volume Control Box that can reduce the handset transmit volume, which may help in some situations.