sandman.com : Knowledgebase

What is a Noise Cancelling Handset and How Does It Work?

Noise Cancelling Handsets are designed to help eliminate 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.

Removing background noise helps in two ways. First, the person on the other end of the call 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 help eliminate paging feedback when there's a paging speaker near the phone.

Noise Cancelling Handsets Are Great For:

  • Factory floors with ambient equipment noise
  • Restaurant 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!)
  • Security sensitive environments such as trading desks or legal offices
    NOTE: If you're serious about security, a Push-To-Talk (PTT) handset is the better way to go.

We Make Noise Cancelling Handsets for Hundreds of Phone Models
Contact Us to see if we can make yours!

How Do Noise Cancelling Handsets Work?

How a Noise Cancelling Handset Works
How a Noise Cancelling Handset Works

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.

Our 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 background 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.

Noise Cancelling Microphone in Handset
Noise Cancelling Microphone in Handset

The picture above shows 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 in the transmitter area to fit the second sound port or potentiometer. 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.

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