Vendors of headsets, telephony devices, and collaboration systems typically highlight a range of features related to noise cancellation in their datasheets. You’ll often come across terms like “acoustic shield,” “active noise cancellation,” “AI noise cancellation,” and many others, all used to emphasize a device’s ability to deliver clear and intelligible audio.
With so much marketing jargon, the actual meaning of these terms can easily get lost. In this article, we break down the terminology and explain what each of these features really means in practical, easy-to-understand terms.
The key to it all: who benefits?
When you read the datasheets of headsets, VoIP phones, and collaboration hardware, there’s a lot of information about the various audio capabilities of these devices. When it comes to noise cancellation, however, it can be difficult to determine what exactly is being described.
There are two primary types of noise cancellation, and the key to understanding them is to determine who benefits from each.
The first, which is generally known as active noise cancellation (ANC), benefits the wearer. ANC is a feature of headsets and earbuds that helps block sounds from the environment. In other words, it benefits the wearer, and not the listeners on the other end of the conversation.
The second type of noise cancellation benefits the remote listener. The general term for this is microphone noise cancellation, but vendors use a wide variety of terms to describe it. Yealink calls it Acoustic Shield Technology (AST), Jabra and Poly call it environmental noise cancellation (ENC), while others simply call it noise cancellation or noise suppression. In all cases, the goal of this feature is to enable the human voice to be picked up by the local communications device and have all other sounds reduced or filtered out before sending the audio to the remote listener. So, it benefits the listeners on the other end of the communication.
Ultimately, both are necessary for clear and effective remote communication.
ANC is a feature that is primarily found on headsets and earphones that uses built-in microphones to detect and analyze ambient noise. It then generates inverse sound waves in the headset that cancel out background noise. The result is that the wearer hears more of what is being played by the headphones (the voice of a remote caller, a videoconference participant, music, etc.) and less of the sounds around them, resulting in less distraction from the surrounding local environment.
ANC is typically more effective with binaural headphones, with either over-ear cups or in-ear buds, which help isolate the user from surrounding noise. It can, however, be employed with monaural earphones as well, with less effectiveness (for obvious reasons).
ANC comes in several variations, depending on the headset or earphone vendor. These include hybrid ANC, adaptive ANC, and others, all of which perform a similar function but do so using differing methodologies and algorithms, achieving varying levels of effectiveness.
Microphone noise cancellation can be achieved using various mechanisms, but all depend on the use of multiple microphones: anywhere from three to five on a headset or up to 16 or more on a room collaboration system. One or more microphones are used to pick up the human voice, which is the sound we want to convey and to be clearly heard on the other end. At least one microphone is used to pick up ambient sound; that is, the environmental sounds in the vicinity of the speaker.
Using a variety of techniques, captured sounds are digitized and then processed by specialized digital signal processors (DSPs), which filter out the noise. This includes office noises like typing and nearby conversations, outdoor noises like wind and street sounds, or even music, clapping, or slamming doors.
There is a broader set of technologies used to achieve microphone noise cancellation beyond ANC, and this is true for several reasons. First of all, unlike ANC, the employment of the technology is not limited to headsets, but is also found on VoIP desk phones, webcams, and collaboration room endpoints and platforms. Second, it can be achieved using either hardware or software and can also be aided by artificial intelligence, which is why we so often see “AI noise suppression” or similar terms in datasheets and marketing materials.
Regardless of how it is achieved, or on what kind of device it is achieved on, microphone noise suppression ultimately enhances the ability of the human voice to be heard by remote participants over all other sounds in the environment.
The following table displays some of the terminology used for these technologies, along with an explanation of what they do and whom they benefit.
You will often see additional terms and features that are related to audio on device datasheets. Such features are typically specialized for particular purposes. These include:
The following table summarizes these features and how they benefit users and endpoints.
Audio is arguably the most important part of any remote communication, whether it uses a headset, IP phone, collaboration endpoint, or mobile device. For this reason, noise cancellation of all types plays an important role in ensuring crystal-clear communications in both directions. Knowing more about what these features are and how they benefit users and their listeners goes a long way toward ensuring that you make the right choices for equipment procurement.
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