ACTIVE BRUSH REDUCTION
Understand the differences and benefits
The ultimate protection against harmful sound.
One common misconception is that all headphones with active noise cancelling are built in the same way. Active noise cancellation is by no means a new technology. It has been in the military for many years but it is not until now that thanks to Guardio Vanguard we can offer this also in hearing protection. Headphones in the consumer market have become very popular in recent years, but everyone is, as I said, not designed in the same way. There are three different types of active noise cancelling, which are sometimes also called noise reduction or simply active noise reduction in Swedish. Feedback, Feedforward and hybrid are the different versions available.
On headphones with Feedback solution, the microphone is located inside the ear cup in front of the speaker itself. This means that the microphone catches up and can analyze the sound in the same way as the ear perceives the sound that one tries to shut out. The great advantage of Feedback is that the active noise reduction better adapts to variations and can more easily correct the signal if necessary. Another great advantage of Feedback headphones is that it provides good protection even if the headphone case itself is not perfectly positioned over the ears. When the microphone is close to the ear itself, the audio signal is adjusted so that as much of the harmful sound as possible is knocked out.
In the feedforward headphones, the microphone is located on the outside of the ear cup. The advantage of this is that the microphone can capture the harmful sound before it reaches the ear and thus gets extra time to analyze the noise and send an optimized sound wave that knocks out the harmful sound. Feedforward headphones also protect better against high frequency sounds of up to 1-2 kHz. The disadvantage of feedforward is that they can send a non-optimized sound wave if you accidentally use their hearing protectors in a way where the ear cups do not sit correctly over their ears.
The most advanced type of active noise reduction is called hybrid. It is the type of technical solution Guardio uses in his hearing protection and simply involves combining feedback and feedforward. So you have double sets of microphones in each ear cup to get the benefits of each solution. Hybrid ANC can suppress sounds in a larger number of frequencies, adapt to and correct errors and is not as sensitive to how the person is wearing the headphones. The signals from the two different microphones are analyzed by the circuit board and calibrated to send the correct mirrored sound wave that knocks out the harmful sound. A solution that thus takes the best of feedback and feedforward.
* = Studie utgiven av The Journal of the Acoustical Society of America .
Active noise reduction with listening
Customize the noise reduction on your hearing protectors to suit your needs where you are right now. Guardio's hearing protection offers listening for your safety. This means that the covers filter out speech from the surroundings. One can continue to listen to music, but if someone calls in the vicinity, the sound from the voices goes through. It is possible to set the covers according to how strong the listener wants. You can do this directly on the hearing protector or through our app.
Explore and understand the functionality a little more closely through our simulator below. By adjusting the level of listening, you determine how much of the surrounding sound is to be released through the music.
This is how active noise reduction works
- 1 - Microphones detect the harmful sound
- 2 - The malicious sound sends to the circuit boards for analysis
- 3 - A mirrored / inverted sound wave is created and sent to the speakers
- 4 - The mirrored sound wave knocks out the harmful sound