What Is Active Noise Cancellation (ANC) and How Does It Work?

You've seen "ANC" on headphone packaging, heard it mentioned in reviews, and maybe even wondered whether it actually does what it claims. Active Noise Cancellation is one of the most useful technologies in modern audio — but it's also one of the most misunderstood. This guide explains exactly what ANC is, how it works, when it helps (and when it doesn't), and how it compares to other types of noise reduction.

Active Noise Cancellation — commonly abbreviated to ANC — is a technology built into certain headphones and earbuds that actively reduces unwanted background noise reaching your ears. Unlike the physical muffling you get from thick ear cups or snug ear tips (which is called passive noise isolation), ANC uses microphones and processing electronics to analyse the sounds around you and generate an opposing signal that cancels them out before they reach your eardrums.

The result is that sounds like aircraft engine rumble, train noise, air conditioning hum, and road traffic are significantly reduced — letting you focus on your music, podcast, or phone call with less distraction, and often at a lower, safer volume.

ANC was first developed for aviation use in the 1970s and 1980s, where pilots needed to communicate clearly over the constant roar of aircraft engines. Consumer versions began appearing in the early 2000s and have since become a standard feature in mid-range to premium headphones and earbuds.

The technology behind ANC is rooted in a principle called destructive interference.

Sound travels as waves — alternating areas of compression and expansion in the air. Every sound wave has a specific shape, characterised by its frequency (how quickly the wave repeats), amplitude (how loud it is), and phase (where in its cycle it currently sits).

Here's the key insight: if you take a sound wave and produce an identical wave that is exactly half a cycle out of phase — meaning the peaks and troughs are perfectly inverted — the two waves cancel each other out. The areas of compression meet areas of expansion, and the result is silence. This is called an anti-phase signal.

ANC headphones do this in real time:

1. Tiny microphones on the outside of the headphones pick up ambient sound — the engine roar, the ventilation hum, the background chatter.
2. Onboard processors analyse that incoming sound and calculate its waveform almost instantaneously.
3. The processors generate an anti-noise signal — a mirror image of the incoming sound, inverted in phase.
4. This anti-noise is played through the headphone speakers alongside your audio, effectively cancelling out the ambient noise before it reaches your ear.

All of this happens in milliseconds. The processing must be fast enough to keep up with constantly changing sounds in real time — which is why effective ANC requires dedicated electronics and battery power.

Not all ANC systems are built the same way. There are three main architectures, and the differences affect how well the system performs.

Feedforward ANC uses microphones placed on the outside of the headphones — facing outward toward the noise source. The microphones pick up ambient noise before it enters the ear cup and use that signal to generate the anti-noise.

The advantage is speed — the system has a small amount of time to process the noise before it reaches your ear. The limitation is that feedforward systems struggle to adapt when the fit of the headphones changes (for example, if they shift on your head).

Feedback ANC places the microphone inside the ear cup — between the speaker and your ear. It measures the sound that actually reaches your ear and adjusts the anti-noise accordingly.

This approach is better at adapting to changes in fit, but has a tighter time window to react to incoming sounds, which can make it slightly less effective at very high frequencies.

Hybrid ANC — used in the best consumer headphones — combines both feedforward and feedback microphones. This gives the processor more data to work with, enabling more accurate and effective noise cancellation across a wider range of frequencies. The Mixx StreamQ D3 and other premium headphones use this approach for the most comprehensive noise reduction.

These two terms are often confused, but they describe quite different mechanisms.

Passive noise isolation is purely physical. It's the reduction in noise you get simply from the headphones sitting over your ears or the ear tips creating a seal in your ear canal. Over-ear headphones with plush ear cups muffle external sound by physically blocking the sound waves. In-ear headphones with silicone ear tips create a seal that reduces how much outside sound gets in.

Passive isolation doesn't require any power, electronics, or processing — it happens automatically as soon as you put the headphones on. It works across all frequencies, including high-frequency sounds like voices and traffic noise.

Active Noise Cancellation works alongside passive isolation — it doesn't replace it. ANC is most effective at low-to-mid frequency sounds (more on that in a moment). Passive isolation handles higher frequencies more effectively. Together, they provide a much more complete noise reduction solution than either achieves alone.

This is why products like the Maplin Bluetooth Noise Cancelling Over-Ear Headphones describe combining active and passive noise reduction — the cushioned over-ear design physically blocks sound while the ANC electronics handle the lower-frequency rumble underneath.

Transparency Mode — sometimes called Ambient Sound Mode or Pass-Through Mode — is the inverse of ANC. Instead of blocking out the world, it uses the headphones' external microphones to pipe ambient sound into your ears, so you can hear what's going on around you without removing your headphones.

Transparency Mode is particularly useful when:

• You need to hear a station announcement or flight boarding call while travelling
• You're in a conversation and don't want to take your headphones off
• You're walking or cycling and need to stay aware of traffic
• You're at a cafe and want the background sound without fully disconnecting from your music

The Mixx StreamQ C4 ANC and Mixx StreamQ D3 ANC both include Transparency Mode alongside ANC, letting you toggle between full noise cancellation, transparent listening, and standard audio with a single button press. The Mixx StreamBuds Ultra DUAL ANC earbuds also feature this functionality in a compact in-ear form.

ANC works best on steady, repetitive, low-to-mid frequency sounds. This is because lower frequency waveforms are longer and easier for the processor to predict and counteract in real time.

ANC is very effective at reducing:

• Aircraft cabin noise and engine rumble (typically 100–400Hz)
• Train and tube carriage vibrations and engine hum
• Road traffic and car engine noise from inside a vehicle
• Air conditioning and HVAC system drone
• Fan and computer cooling noise (useful when working at a desk)
• Constant background hum in offices

ANC is less effective at blocking:

• Sudden, sharp, or unpredictable sounds (a door slamming, someone shouting)
• High-frequency sounds — human speech, music from nearby, sharp clicks
• Complex, rapidly changing noise (a crowded pub or marketplace)

This is why ANC headphones don't make you completely deaf to the world — and why that's actually by design. Completely sealing out all sound would be both technically very difficult and potentially unsafe.

For unpredictable or high-frequency sound, passive isolation from a good fit and quality ear cups or tips will do more of the heavy lifting.

This is one of the most common questions about ANC. The short answer is: on quality headphones, the impact is minimal. On cheaper implementations, you may notice some artefacts.

The "hissing" issue: Some ANC headphones — particularly older or budget models — introduce a faint background hiss or pressure sensation when ANC is active. This is caused by the noise-cancelling circuitry introducing a small amount of noise of its own. Good ANC implementations keep this well below audible levels.

The "pressure" feeling: Some people notice a slight sensation of pressure in their ears when ANC is active, even in a quiet environment. This is the anti-noise signal interacting with your eardrums, and it's entirely harmless — though some people find it mildly uncomfortable at first.

EQ changes: In some headphones, activating ANC can alter the tonal balance slightly — some implementations boost bass when ANC is on, while others maintain a flatter response. Premium headphones like the Mixx StreamQ D3 ANC include app-based EQ controls via the MIXX Control App, allowing you to fine-tune the sound profile to your preference regardless of whether ANC is on or off.

Yes. Because ANC requires active electronics and processing, it uses battery power. This is one of the key practical differences between ANC and passive noise isolation.

Most ANC headphones are Bluetooth wireless models with built-in rechargeable batteries. The ANC circuitry draws from the same battery as the wireless audio, which means:

• ANC reduces battery life compared to using the same headphones without ANC enabled. The amount varies by model and implementation.
• When the battery dies, ANC stops working — though most ANC headphones can still be used in passive wired mode (via a 3.5mm cable) when the battery is flat.
• Charge them regularly to make the most of ANC on long journeys or commutes.

Battery life varies considerably between models. The Mixx StreamQ C4 ANC delivers up to 40 hours of wireless playback with ANC enabled, while the Mixx StreamQ D3 ANC offers up to 45 hours — outstanding figures for daily commuting. Both also feature quick charge: 15 minutes of charging provides 8 hours of playback, which is ideal if you've forgotten to charge overnight.

Both form factors can deliver excellent ANC, but they have different strengths.

Over-ear (circumaural) headphones physically enclose your entire ear, creating a large air cavity between the speaker and your ear canal. This gives the ANC system more space to work with, and the large ear cups contribute significant passive isolation. The result is typically the strongest overall noise reduction — which is why over-ear ANC headphones are the preferred choice for long-haul flights and open-plan offices.

They're also generally more comfortable for extended listening sessions, with soft ear cushions and adjustable headbands that distribute weight evenly.

The trade-off is portability — over-ear headphones are larger and require a case or bag. Models like the Mixx StreamQ C4 ANC and Mixx StreamQ D3 ANC address this with foldable designs and included carry cases.

True wireless ANC earbuds sit directly in the ear canal, creating a seal that contributes strong passive isolation. Modern ANC earbuds have improved dramatically and can rival over-ear headphones for noise reduction in many environments — particularly at lower frequencies.

Their key advantage is portability: they're tiny, lightweight, and disappear into a pocket-sized charging case. They're ideal for commuting, gym use, and anyone who finds over-ear headphones uncomfortable or impractical.

The Mixx StreamBuds Ultra DUAL ANC TWS Earphones offer up to 7 hours of playtime per charge (28 hours total with the charging case) alongside full ANC and Transparency Mode. They also feature quick charge, giving 2 hours of playback from just 15 minutes of charging.

ANC headphones offer the most benefit in specific situations and for certain types of user.

Commuters — The daily train, tube, or bus commute is one of the best use cases for ANC. The steady engine noise and vibration is exactly the type of low-frequency sound ANC handles best, and the ability to listen at lower volumes on a noisy commute protects your hearing over time.

Frequent flyers — Aircraft cabin noise is notoriously fatiguing. ANC headphones are standard equipment for many regular travellers, reducing cabin drone so you can sleep, work, or enjoy entertainment without cranking the volume.

Open-plan office workers — Concentrating in a busy office is one of the most common drivers behind ANC headphone purchases. The steady hum of HVAC systems and the murmur of background conversation are both well within ANC's comfort zone.

People sensitive to noise — ANC headphones have gained recognition as a helpful tool for people with sensory sensitivities, including those with autism, ADHD, or anxiety, for whom constant background noise can be particularly draining. The Mixx StreamQ C4 is recommended by the National Autistic Society.

Remote workers — Working from home with noise around you — family, traffic, or neighbours — can make video calls and focused work difficult. ANC headphones reduce distraction without requiring a soundproofed space.

Students — Whether in a library, a noisy hall of residence, or a coffee shop, ANC headphones help students focus and block the distractions that come with shared spaces.

Mixx StreamQ C4 ANC Over-Ear Wireless Headphones A highly capable ANC headphone at an accessible price point. Features active noise cancellation, Transparency Mode for safe situational awareness, and up to 40 hours of battery life with ANC enabled. Quick charge delivers 8 hours of playback from 15 minutes of charging — ideal for commuters who regularly forget to charge overnight. Foldable design with adjustable headband and tilting ear pads for travel. Hands-free calling via integrated controls. Recommended by the National Autistic Society.

Mixx StreamQ D3 ANC Over-Ear Wireless Headphones The premium step up in Mixx's over-ear ANC range. Offers up to 45 hours of wireless playtime with ANC active, the same 15-minute quick charge for 8 hours of use, and full Transparency Mode. Includes support for voice assistants (Siri and Google Assistant), wired listening via 3.5mm cable, and compatibility with the MIXX Control App for personalised EQ and settings. Comes with a deluxe carry case. The best choice for frequent travellers, long-haul flights, and serious commuters who want premium ANC performance without a flagship price tag.

Maplin Bluetooth Noise Cancelling Over-Ear Headphones Maplin's own-brand ANC over-ear offering. Combines active and passive noise reduction with Bluetooth 5.3 connectivity, up to 25 hours of battery life, and a 3.5mm audio port for wired use on aircraft. A solid, budget-friendly entry point for anyone wanting to try ANC for the first time.

Mixx StreamBuds Ultra DUAL ANC TWS Earphones True wireless ANC earbuds featuring both Active Noise Cancellation and Transparency Mode in a compact, portable package. Up to 7 hours of playtime per charge, with 28 hours total from the zinc alloy charging case. Quick charge gives 2 hours of playback from 15 minutes. Includes Clear Voice Technology for hands-free calls, three sizes of ear cushions for a secure fit, and compatibility with the MIXX Control App. A great choice for commuters and anyone who finds over-ear headphones too bulky for everyday carry.

Maplin In-Ear Headphone Kit Compact Bluetooth 5.3 earbuds with noise-cancelling deep bass and up to 6 hours of playback. Rechargeable via the included charging case. A straightforward, affordable entry-level option for everyday use.

Maplin Bluetooth Noise Cancelling Headphone Combo Kit A bundle that includes both the Maplin over-ear noise cancelling headphones and the Maplin Bluetooth earbuds — ideal if you want the flexibility of switching between in-ear and over-ear depending on your activity.

Can I use ANC headphones without audio playing? Yes. Most ANC headphones allow you to activate noise cancellation even when no music or audio is playing. This is useful in situations where you simply want to reduce ambient noise — on a flight, in an office, or while studying — without necessarily listening to anything.

Is ANC safe to use? Yes, ANC is entirely safe. The anti-noise signal is designed to cancel specific external frequencies; it has no effect on your hearing health. Using ANC can actually be beneficial for hearing over time, as it allows you to listen at lower volumes in noisy environments while still hearing your audio clearly.

Do ANC headphones completely block all sound? No. ANC reduces ambient noise significantly but does not create complete silence. It's most effective at steady, low-frequency sounds. High-frequency and unpredictable sounds will still be partially audible, especially without a good passive seal.

Can ANC headphones be used on flights? Yes — they're arguably one of the best things to bring on a long-haul flight. Most ANC headphones include a 3.5mm audio cable so you can connect to the in-flight entertainment system, and the ANC works independently of the wireless audio.

Shop All Headphones at Maplin →

Shop Over-Ear Headphones →

Shop Wireless Earbuds →