Why Active Noise Cancelling Headphones Make Noise

Noise Cancelling
Written By Soundsight

If your active noise-canceling headphones seem to be creating a sound as you use them, it’s likely due to how they operate. Many times it’s due to poor implementation, firmware issues, a resistor and capacitor that slows the flow of electricity in the circuit, or even flawed microphones or noise-canceling processors.

In this article, I explain why active noise-canceling headphones make a noise, whether caused by an internal battery or a noisy microphone, what types of sounds active noise-canceling headphones make and if you should be worried about your ANC headphones making a noise.

What are active noise-canceling headphones, and why do they generate noise?

Before explaining why ANC headphones produce noise, it is important to understand active noise cancellation and how it works. The concept of active noise cancellation is that the headphones pick up the ambient noise around you, pass it through a microphone and processor, and playback the opposite signal to cancel out the sound waves hitting your eardrums.

Why ANC headphones make a noise

No ANC system is perfect, and there is a lot of room for error in a circuit with a few processes and various electrical components. So, the reasons why the ANC headset makes noise are one of the following:
1) The microphone array on the headset inaccurately records noise and plays back the reverse signal with a slight variation.
2) The headset’s DSP chip cannot produce clean sound due to electrical interference from the headset’s components, a bad algorithm, or the DSP chip’s software.
3) The DSP chip is defective
4) The headphones’ electronics are defective and constantly emit a small amount of noise that is audible to you.
5) The ANC headset has multiple microphones that generate noise in one of the following ways:
a) The same noise is recorded by multiple microphones
b) A clear sound is recorded incorrectly, or the sound is clipped
c) The microphones are clogged with dust and do not work properly.
4) Headphones with Hybrid or Feedback ANC technology generate feedback noise
5) There is white noise from too many microphones due to EMI or electrical interference.

What noises do ANC headsets generate?

Active noise-canceling headphones can unintentionally generate all types of noise, including:

  • Static noise
  • Hissing
  • Popping
  • Crackling
  • Feedback noise
  • Buzzing and hums
  • White noise.

Interestingly, even though ANC headphones generate some noise, it is usually imperceptible and compensated by a huge noise reduction in the first third of the sound spectrum.

Hissing sound

The most common, and probably most annoying, noise generated by ANC headphones is a high-pitched whistling sound that occurs in the high-frequency range. This noise compromises the passive sound isolation properties of the headphones, causes ear fatigue when using ANC headphones without music, and makes the listener uncomfortable when the volume is too low.

Buzzing or humming

Another common noise produced by active noise reduction headphones is known as buzzing or hum. Deep hum is usually generated below 50 Hz and often affects the headphones’ sound response. This occurs due to poor wiring, electromagnetic interference, the way electricity is generated, or a poor analog connection. Deep hums are also the noises responsible for making you feel sick when using ANC.

White noise

White noise, generated by the ANC circuitry itself, is specific to a type of active noise cancellation technology. This noise can only be heard when the ANC function is activated and is typically subtle. It occurs most regularly in hybrid headsets due to electrical interference from too many noise-canceling microphones in the headset. LINK HERE

FAQ regarding ANC headphones that make noise

Should I be concerned about the noise my ANC headphones make?

No. Noise from your ANC headphones is not a problem. You should be concerned if the noise is noticeable when listening to music or in a quiet environment. When Active Noise Cancellation operates in a quiet environment, it should not make much noise. You may hear some humming or static, but this is usually caused by the ANC circuitry and internal components.

Do all ANC headphones make a noise?

Not all active noise-canceling headphones generate noise, so if your headphones make a noticeable sound in a quiet environment, you should take them to the store and see if they can be exchanged for another pair. Feedforward and Feedback ANC headphones don’t generate noticeable noise.

High-end headphones, particularly Apple’s AirPods Max, Bowers & Wilkins’ PX7, and Beyerdynamic’s Lagoon Traveler, offer a quiet and comfortable listening experience, even without music.

How much white noise do active noise-canceling headphones generate?

This is a very subjective question that is difficult to answer accurately. Not all ANC headphones generate noise or white noise in particular, and the amount certainly varies depending on the model and the quality of the noise-canceling technology. Except for very high-end ANC headphones, most ANC headphones emit static noise that is often noticed the longer you listen to music.

The active noise reduction system can produce a maximum of 5 dB of noise, but it’s usually close to 1 dB or even 0 dB. The white noise generated is not enough to cover your music. Still, when your music is filled with mellow sounds like a soft piano, you can hear the noise generated by the ANC system. Also, as soon as you turn off the active noise cancellation, the noise stops instantly.

Conclusion

While they make some noise, active noise-canceling headphones should not be a problem if you use them in noisy places where they are needed. It’s unlikely that high-quality ANC headphones can compensate for a poor listening experience. But there is a point where even the best models have some flaws.

If your ANC headphones bother you a lot or want a quality product, check out this list of the best noise-canceling headphones. You can also check this article on using ANC headphones without music that I wrote because I know how annoying it can be to use a pair of noise-canceling headphones that makes noise. LINK HERE