Just a few days ago, one of our customers asked me a question. He said that when buying noise-canceling earbuds on Amazon, the product details page would write about feedforward active noise cancellation and hybrid active noise cancellation. . So what exactly is the difference between these noise reduction modes? This is a very good question, and it is very suitable for taking it out separately and explaining what is single-feed noise reduction? What is Hybrid Active Noise Cancellation?
Nowadays, daily life is full of all kinds of noise. To avoid the trouble of noise, active noise-canceling earbuds have come out. Active noise reduction is a technology applied to noise-canceling earbuds. It collects ambient noise through the pickup microphone above the earbuds, converts the noise collected by the microphone into a digital signal, and calculates a Noise that is the opposite of sound waves, which has the effect of eliminating noise.
But now many people are confused when they look at the introduction on the product details page when they buy active noise-canceling earbuds. Some say that this earbud support feed-forward active noise reduction, some say that it uses feed-back active noise reduction, and some more expensive earbuds say that it supports hybrid active noise reduction, which is very impressive Puzzled.
In fact, before 2019, most products of active noise reduction earbuds used single-feed active noise reduction. In the second half of 2019, Hybrid active noise reduction technology began to be applied in headphone products. Now that the basic knowledge is understood, we need to see what is single-feed noise reduction and hybrid active noise reduction.
TIPS: The product description only introduces that the earbuds as "active noise cancellation" are mostly single-feed noise reduction.
Feedforward Active Noise Cancellation
Let's talk about feed-forward active noise cancellation first. In the early days, most of the low-priced active noise-canceling earbuds used feedforward active noise canceling, because its structure is very simple, only one microphone needs to be configured on the outside of the two earbuds to detect the surrounding environment. noise. This solution ensures that the sound from the headphone speakers does not interfere with the nose-picking microphone. This noise reduction solution is very straightforward. After the microphone collects the noise signal, the processor directly processes it, and the headphone speaker emits reverse sound waves to neutralize the noise. This is a relatively simple and low-cost noise reduction solution. It cannot filter some sudden noises well, and there will be noises that cannot be filtered in time.
Feedback Active Noise Cancellation
Feedback active noise reduction and feedforward active noise reduction are both single-feed noise reduction structures. Feedback active noise reduction puts the noise-collecting microphone near the headphone speaker, and the noise collected by the feedback active noise reduction scheme is closer to what the human ear can hear. In this way, the noise reduction effect will be slightly better than the feedforward type. However, the disadvantage of feedback active noise reduction is also very obvious, and it is prone to high-frequency howling. At the same time, music sounds similar to noise will be treated as noise, which will cause a certain degree of music distortion
Hybrid Active Noise Cancellation
TIPS: Hybrid noise-canceling earbuds are clearly stated in the product introduction
Hybrid active noise reduction is to use two or more microphones for noise monitoring, but these microphones do not allow them to monitor external noise at the same time, because if they all monitor external noise, it will bring a 1+1 <2 effects. Doubling the number of microphones brings additional power consumption and data operations, as well as 1+1<2 negative power consumption, which is not worth it. The hybrid active noise reduction is to arrange multiple microphones outside the earbuds and near the speaker, some of which are used for feed-forward noise reduction and the other for feedback noise reduction. Feed-forward microphones monitor ambient noise like single-feed noise-canceling microphones, and feed-back microphones monitor noise that can be transmitted to the ear after filtering.
The two systems cooperate for noise cancellation, combining the advantages of the two and offsetting the disadvantages so that the Hybrid active noise reduction can enable the earbuds to achieve a deeper noise reduction effect. Of course, this technology also has shortcomings. One is that the design is difficult to implement, and the other is that it will bring higher costs.
The active noise reduction technologies we can see on the market are the three mentioned above. Hybrid active noise-canceling earbuds are the most effective, but more expensive. The single-feed active noise-canceling earbuds are not as effective as the Hybrid, but they are less expensive. If you only use it in a quieter indoor environment most of the time, then single-feed active noise-canceling earbuds can already meet your requirements. If you need to be often in a noisy environment, then don't worry about money, or buy a pair of hybrid active noise-canceling earbuds.