There is always a variety of helplessness in living and working in big cities. Take our small family (my wife and I) as an example. We spend 2.5-3 hours a day on commuting. These times in daily transportation are often accompanied by noise. I have passive noise reduction earplugs to keep me away from noise, and my wife does not have such items to ensure cleanliness along the way. The road to and from work is long and boring. If you are associated with noise, it will not only cause hearing damage, but also cause nervous tension. Therefore, engaging in a noise reduction headset for my wife has also become a focus of my purchase of new products this year. Although passive noise cancelling headphones are relatively abundant on the market, the compatibility of the kidneys with no 3.5 mm jacks is almost equivalent, so I turned my attention to active noise reduction products that support Bluetooth + noise reduction. In this type of product, Bose's noise reduction technology is unique. Bose's new products this year are the QC30 and the QC35. If you do not consider the sound quality and pay more attention to portability, the QC30 is the natural choice. However, before the official start of the sales order, please allow this fat man to don't have a donkey once again. Let's start with the Bose company. The Bose brand originated from the founder Amar Gopal Bose, an Indian-born successful entrepreneur and even a successful scientist. A. Bose received a full course of education from bachelors to doctors at MIT, while in the industry he used nonlinear systems and D. The research work in the class of signal amplifiers is well known and is an honorary member of the IEEE (Fellow, whose status is similar to that of Chinese academicians). In fact, if you look at the academic field, A. Bose is not only successful in his own right, but he is also famous. His mentor is Mr. Li Yurong, who taught at Tsinghua University after earning his doctoral degree in MIT in the 1930s. One of China’s early major electrical engineering experts, who had been teaching and researching at MIT since the War of Resistance against Japan, was one of the earliest honorary members of the IEEE. His joint tutor is Wiener, who has the title of “Father of Cyberneticsâ€. Weiner is Russell (mathematical logic giant), Hardy (British mathematical analysis genre bearer) and Hilbert (modern mathematics undefeated king) three masters. s student. Mr. Li Yurong’s doctoral advisor (which can be called Bose’s teacher ancestor?) is Bush with the title “Father of the Information Ageâ€. In the figure above, from left to right, Li Yurong, A. Bose, and Wiener, and on the blackboard, the famous Lee-Wiener Network. It seems that, unlike the founder of the general company, Bose's founder, A. Bose, is no doubt more like a scientist - he himself thinks so - he is still a professor of MIT until the age of 82, and The majority of Bose’s non-voting equity was donated to MIT to use its proceeds for scientific research. Based on the above facts, it is not difficult for us to understand why A. Bose insists that Bose is not listed. The original intention of Bose was to love scientists in the field of radio and high-fidelity electrical engineering. Scientists often have long-term goals for the medium-term or long-term. Plans, even if they are engaged in sideline operations, will be hindered by the medium and long-term plans that will be imposed on shareholders after listing. A well-known example is Bose's Auto-Suspension Research project, which is a technology for car suspension (yes, you read it right), known as a magic carpet, and the video is here. The project lasts for 24 years. If the company is listed in the general public, the project will be suspended due to long-term continuous investment due to no return. It is also worth noting that in addition to the founder A. Bose, many of Bose’s top executives are also signal processing professionals – such as Bose’s 1985-2001 president, Sherwin Greenblatt, who was A. Bose’s student at the signal amplification The field is also quite successful. In summary, Bose not only has Geek's blood, but also the founder and a considerable number of company executives are professional and even authoritative in the field of signal processing. Therefore, we can understand why Bose Company adopts the characteristic product strategy rather than the cost-effective product strategy in the audio field. Bose Company sells algorithms and does not sell powerful pills. Therefore, it adopts this main effect enhancing strategy. It is just what it should be. Bose's active noise reduction technology is no different from other manufacturers. After using microphones to collect ambient noise, the signal processing circuit is used to reverse the collected environmental noise along with the music, thereby reducing noise. The story of the invention of Bose noise reduction technology has already been introduced in Lin Zhihu's big post, so I will not go into details here. Although everyone in the juggernaut will change, the best that can be changed is the professional. Although active noise reduction products enter the blowout stage, major (even small, such as headlines) audio manufacturers have launched their own initiatives. Noisy headphones, but if the noise reduction effect, Bo is still a trend. In fact, in a nutshell - Bose's noise reduction level is higher than that of other friendly companies. The figure below shows the actual noise reduction graph taken from a Bose patent. It can be seen from the figure that the level of Bose active noise reduction is at the highest level of 20 dB. This level corresponds to a frequency of 150-500 Hz, which is exactly the medium-low frequency and A small part of the vocal area. After more than 500 Hz, the noise reduction level of the headphones will drop rapidly, and the noise reduction capability can only reach 5 dB at 1000 Hz. It can only be regarded as better than nothing. In recent years, the noise reduction parameters from competing products have risen again and again, and there are already many active noise reduction products that can reach 20 dB or even as high as 30 dB. However, the actual use results are still not as good as Bose (such as a Japanese A-word manufacturer). The noise reduction parameters became the same girl as the frequency response data. Every manufacturer who wants to make a difference in the active noise canceling headphones should provide the relationship between noise reduction ability and frequency only at the highest noise reduction level. Well, after the three papers don’t have any donkeys, here’s the QC30 hands-on experience. Compared to its predecessor, the QC20, the QC30's packaging is much larger. This is also related to the form of the earphones. The QC20 is an earbud. While the QC30 is also an earbud, the noise reduction box is integrated into the neck ring. Because of this, the neck ring cannot be bent, so you have to use a larger box and a larger carrying case (this is a portable box...). However, compared to the QC35, the QC30 is not to be hung on the neck when not in use, but it is still a little more convenient. Also worth mentioning is the color, and QC20 have to come up with a strange color to different, QC30's color is very low-key, basically a solid color - this kind of color is full of straight male feeling, it is not very good for the wife Suitable...... The earring's neck ring is treated like a skin, the opening key seems to have a certain drainage effect, and the charging port also has a rubber seal. Although Bose did not give the QC30's waterproof rating, I believe that since it came to this form, it means that the QC30 is certainly equipped with a certain degree of waterproof capability. The positioning of the QC30 is likely to be the level of daily use to light exercise. The style of earplugs and wire controls did not change much from that of the QC20. It does not seem that the neck ring body was waterproofed. This is why I think that the QC30 is not suitable for moderate or heavy exercise - although Sweat won't affect the neck ring, but the interface near the earphones will become a slightly weaker link. Overall, the QC30 has maintained Bose's excellent workmanship in the United States in terms of appearance, and is quite satisfactory. From the effect of noise reduction, QC30's biggest selling point is not the improvement of noise reduction performance, but the use of software to control the noise reduction level so that certain warning sounds can be heard, thus controlling the dangers in certain specific use environments. After connecting the mobile phone through Bose software, you can adjust the noise reduction level through the above interface. The maximum value of noise reduction level is basically equal to the noise reduction level of QC20. Generally, when it is adjusted to 12 o'clock, the external sound can basically be heard (in other words, the noise reduction effect before 12 o'clock is not obvious). However, this does guarantee the security of using noise-reducing headphones in certain scenarios. (But this feature is really useful for girls whose application scenarios are limited to public transport...) In addition, the limitations of noise reduction in sports types are mentioned. Since the QC30 uses an external microphone to collect noise, it is basically impossible to eliminate the signal overload peak due to wind noise during the riding process. Therefore, it is hoped that the friends used during the ride will come Say, unless you drop the table, QC30 basically does not have noise reduction effect. Let's talk about the QC30's sound quality, but there is really nothing to say, because it is really lackluster - IF dry without emotion, high-frequency stuffy stuffy, low-frequency tightening did not dive, in short, a word - frustration. On the whole, besides the pleasure of pumping air out of your ear at the instant of noise reduction, the QC30 does not have any pleasure when playing music. This is not as good as the previous generation QC20. The thief thought that even if the apple was randomly assigned to the white, the sound quality was better than the QC30, which wasn't required to do so. From the above description, it can be seen that the QC30 should be a daily-light exercise-level noise-reducing earphone with male users as the main target group. The sound quality of this headset is a short board, and the controllability of portability and noise reduction level is an advantage. For female users or those who have certain requirements for sound quality, it is best to think about the QC35. If there is no requirement for active noise canceling headphones in the near future, you may wish to wait. With the joint application of Bluetooth and active noise reduction, the distance between Bose and other headphone manufacturers has been shortened, and in the next few years, it will be a hundred flowers for you to sing. Scenes. The fat man cry blood to tell you the value of the above points, many do not say, New Year's goods to buy inappropriate, I want to continue to go back to the motherboard. PCD Drills
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