According to a recent survey in 2020*, 94% of workers experience some form of ambient noise during calls. This is an increase from 71% of workers in 2017. Noise not only impacts a user’s ability to concentrate and focus on the task at hand, but without a good quality noise-canceling microphone it also impacts other participants on conference calls.
Poly’s headsets are used in the most demanding environments where clear audio is critical, such as emergency dispatch and command and control applications.
When considering noise canceling headsets it’s important to note that different technology is used to reduce noise for the headset wearer and hence acts on the receive side (typically this is active noise canceling) compared to noise canceling for the far end, which acts on the microphone (transmitting) side.
*Persona Research October 2020 Factworks
- Receive Noise Reduction
- Transmit Noise Reduction
Passive Noise Reduction
The simplest form of receive noise reduction comes from the fact any stereo headset provides a physical barrier to the ear canals and hence reduces the level of audio that can be heard.
The amount of noise reduction will depend on may factors for example a headset, such as the Voyager 8200 UC, that covers the ear completely provides better noise reduction compared to one that sits on the ear. Leatherette ear cushions provide a greater acoustic seal to the ear and will provide better noise reduction compared to foam ear cushions.
Headsets with earbuds that sit inside the ear, such as the Voyager 6200 UC, provide a greater isolation from external sounds. An advantage of the Voyager 6200 UC headset is that it can still be used with one ear bud removed allowing users to still hear what’s going on around them.
Active Noise Reduction
For greater noise reduction passive noise isolation can be combined with active noise cancellation. Poly offers one of the largest range of Active Noise Canceling headsets in the market.
There are three types of ANC:
- Feedback ANC: With Feedback ANC microphones are placed inside the ear cup and monitor what the user hears.
- Feed-forward ANC: Feed-forward ANC is rarely used on its own in headsets as the ANC microphones are placed outside the ear cup and monitor the background noise making it sensitive to wind noise, etc.
- Hybrid ANC: ANC microphones are placed both inside and outside the ear cup (requires 2x more microphones compared to feedback ANC) and monitors both what the user hears and the background noise.
Noise Canceling Microphone
To ensure that background noise is not picked up by the headset microphone, which could interrupt the call, many Poly headsets include noise canceling microphone booms. These booms include a special directional microphone that picks up sound in a specific pattern that is focused towards the user’s mouth. Sounds that come from all directions, such as background noise, are picked up with less amplitude and therefore are heard by the far end at a reduced level.
To provide the best noise reduction the optimum position for a noise canceling microphone boom is directly in front of the user’s mouth. Since this can be distracting to the user, as its in their eyeline, a compromise is made so that the microphone boom is typically located at the corner of the mouth. The microphone booms can be bent so that the microphone is in the correct position. For the Poly EncorePro 700 Series an extendable microphone boom is used to provide the best placement.
Close Conversation Limiting
Using proprietary Digital Signal Processing (DSP) Poly can further reduce any transmit noise. The Poly Savi 8200 Series use a noise canceling microphone boom plus a feature called close conversation limiting, which is designed to reduce the level of nearby conversations. The actual level of noise reduction can be configured via Poly software.
Discrete Microphone Boom
The Voyager 5200 UC, designed as an on-the-go product, includes a discrete microphone boom that is great for indoor or outdoor use. Windsmart® technology and a unique DSP is used to reduce disruptive wind noise for outdoor use.
Boomless Design Noise Canceling
For products without a microphone boom such as the Voyager 6200 UC and Voyager 8200 UC, four microphones are used along with beam-forming technology to focus on the user’s voice while minimizing background noise.
Poly Acoustic Fence technology
Transmit noise reduction can be enhanced when additional, physically separated microphones are added, such as those on Poly headsets with Acoustic Fence technology.
Single additional microphone: Poly’s Acoustic Fence technology, as found in the Blackwire 8225, uses a long noise canceling microphone boom with an additional microphone located on the ear cup. This additional microphone picks up the background noise and using DSP this noise is minimized from the user’s voice.
Multiple additional microphones: The Voyager Focus 2 provides even greater transmit noise reduction despite its shorter microphone boom. In this implementation Poly’s Acoustic Fence technology uses four microphones in total, two microphones on the boom and one on each ear cup, to create a virtual pick up bubble focused at the front of the user’s mouth. Anything outside of this bubble (typically noise) is ignored.