Noise-Cancelling Headphone Terminology and Specifications
May 1, 2023 • 10 min reading time
Noise-cancelling headphones are incredibly popular for every group of people, but they are also quite complex. Anyone new to the headphone world may find themselves struggling to understand what each specification means, and making heads or tails of the jargon can be a daunting task. Whether you are interested in making an informed purchase decision or simply want to better understand a pair of headphones you already own, you’ve come to the right place.
Understanding the Vocabulary of Noise-Cancellation
As noise-cancellation is the main draw of noise-cancelling headphones, it should be the first thing people understand about this specialty product. There are two ways headphones can perform in this area: passive noise cancellation and active noise cancellation.
Passive Noise Cancellation
Headphones that make use of passive technology are commonly referred to as noise-isolating headphones instead. Noise isolation involves the structure of the headphones, such as extra padding or full ear cups, to limit the amount of surrounding noise that can be heard.
Passive noise-cancelling technology is found in both on-ear headphones and over-ear headphone varieties. A power source is not needed for passive noise cancelling.
Active Noise Cancellation
Active noise cancellation will require a power source (either a battery or wired connection) to function. This is because it uses advanced technology built into a headphone’s microphone to block out surrounding noises.
The basis of active noise cancellation is this: when a sound from the environment is detected, the headphones will produce a noise in response that cancels out the sound.
Headphones can make use of active noise cancellation and passive noise isolation simultaneously to block out sound, and these models will provide the most immersive experience if you want to completely isolate your audio from the environment.
Understanding Terminology Related to Noise-Cancelling Headphones
Noise-cancelling headphones, and many other types of headphones for that matter, will include the following values in their specifications list. An understanding of them can be achieved with just a little bit of time.
A decibel is a measurement of sound pressure; this is essentially the volume or intensity of a sound. A higher decibel value is indicative of a louder sound.
The frequency response value of a pair of headphones is measured in Hertz (Hz), and it represents the range of frequencies that can be produced. A wider range is ideal for this value, as it will be able to produce low bass notes and high treble notes with clarity. Most headphones can produce all sounds in the range of human hearing, which is 20 Hz to 20,000 Hz.
Total Harmonic Distortion (THD)
Total Harmonic Distortion is a percentage value that represents distortion introduced by the headphones. Distortion has a negative impact on the sound quality of whatever you are listening to. As a result, a THD value of less than 1% is ideal to be confident in the quality of the headphones.
Impedance is measured in Ohms (Ω) and is representative of the electrical resistance the headphones have. A lower impedance value (below 50Ω) means less work for the drivers inside the headphones, and the headphones can therefore be used with devices like smartphones. Higher impedance headphones will need to be used with an amplifier for the audio to come across.
Sensitivity of a pair of headphones is measured in decibels per milliwatt (dB/mW). This value represents how well headphones produce sound from an electrical signal. Headphones with higher sensitivity use less power to produce louder sounds when compared to low sensitivity models.
Understanding Wireless Connectivity Vocabulary
Wireless connectivity is built into most models of noise-cancelling headphone on the market. However, if you don’t understand what the terms mean, you won’t be able to choose the right pair for your needs.
Bluetooth is a simple word for a fairly complex process. It is a technology that allows wireless audio streaming between compatible devices. A Bluetooth version, such as Bluetooth 5.0, is indicative of the headphone’s capabilities, such as wireless range and data transfer rates.
Bluetooth headphones support various codecs, including SBC, AAC, aptX, aptX HD, and LDAC. These codecs are responsible for the compressing and decompressing of audio files for transfer. They minimize latency and ensure the sound quality is the best it can possibly be.
Multi-point connectivity is an extension of Bluetooth capabilities. It means that you can connect your headphones to multiple compatible devices simultaneously, including your smartphone, laptop, and more. This feature allows you to switch between each device seamlessly, rather than needing to pair the Bluetooth to the device independently each time.
The wireless range of Bluetooth headphones describes the amount of distance that can exist between the headphones and the source of device before the quality deteriorates or the connection is lost entirely. Walls and other obstructions may affect the range.
Understanding Terminology for Battery Life & Charging
Understanding battery life and the types of charging that are available to noise-cancelling headphones is necessary for ensuring you purchase the most suitable pair of headphones.
Battery life, represented in hours, indicates how long the wireless headphones can function before requiring another charge. This can range anywhere from 6 hours to 84. In general, a longer battery life is more desirable.
USB charging is the most common method for charging wireless noise-cancelling headphones. USB-C is the most common adapter, but it can come in other forms too.
Fast charging is a feature that allows you to get hours of playtime with just a short charging session. The exact specifications will vary by brand and model, but it can be a lifesaver when your headphones have run out of battery when you need them.
Wireless charging is a second option that you can have for restoring battery life in wireless headphones. Rather than connecting the headphones to a power source with a cord, a wireless charging pad or dock is used instead. This helps to reduce the number of accessories you need to keep track of.
Understanding the Terminology of Additional Features
There are a number of additional features that may be integrated into a good pair of noise-cancelling headphones. Many of them aren’t intuitive, so they are worth mentioning.
Ambient mode, also termed transparency, is a feature that allows you to temporarily disengage the noise-cancelling effects of the headphones to communicate with someone, listen to announcements, or for safety reasons while exercising outdoors.
Compatibility with Voice Assistants
Voice assistant compatibility means that the noise-cancelling headphones can be controlled hands-free through voice-activated assistants such as Siri and Alexa.
If noise-cancelling headphones come with app support, this means the brand offers a companion app that you can download onto your smart phone and use to control your music playback and other settings on your headphones.
An auto pause/play feature is exactly what it sounds like: the headphones are built with smart sensors that can automatically pause your audio when the headphones are taken off, and resume playing when they are put back on. This is the best feature to have when you frequently need to be able to pay attention to something else on short notice.
Foldable vs Swivel Design
Both foldable and swivel headphone designs allow for more compact storage, but they mean different things. A swivel means the ear cups can be rotated to lay flat on a surface, and foldable headphones will fold in at a section on the headband to take up less space and fit into storage bags or cases.
Water Resistance Rating
Many pairs of noise-cancelling headphones will be associated with a water resistance rating. It can look like IPX4, IPX6, and more. The higher the number, the more resistant the headphones are to water and dust damage. Higher ratings will translate to headphones that are safer for use during workouts and rainy weather.
Sound Profile Customization
Sound profile customization means you can change how your music comes out of your headphones by adjusting the equalizers. You can choose to have a balanced audio output or opt for a base-heavy profile.
Automatic Power Off
Auto power off is a power-saving feature that is incredibly common for wireless noise-cancelling headphones. After a pre-determined period of inactivity (30 mins for example) the headphones will shut themselves off to conserve battery.
Although noise-cancelling headphones are associated with a number of unique and complex terms and specifications, anyone who takes the time to learn what each thing means will be well-prepared to make an informed buying decision with confidence.