Main features and unique new technologies of loudspeaker boxes of well-known foreign companies
JBL Corporation
The characteristics of the speaker are: high power, 200-300W; high sensitivity, maximum sound pressure level of 110dB or more; good frequency response, flat frequency response and excellent transient characteristics.
Unique new technology:
(1) The pole core of the speaker woofer is quite thick, and the pole core is hollow with a wire-cut insert. This specially designed pole core reduces the weight of the speaker and facilitates heat dissipation, which is designed to increase power handling.
(2) The flat-line voice coil is an advanced technology that was invented by JBL. Originally used on woofers, and later tweeters are also commonly used, both aluminum and copper. The flat line has a high duty factor and high magnetic void utilization, which is intended to improve sensitivity. According to the test, in the same magnetic circuit, the flat-line voice coil can increase the sensitivity by about 1 dB than the round-line voice coil.
(3) The titanium diaphragm dome unit was also the first to succeed in JBL. The Young's modulus of the titanium material is superior to that of the aluminum material. The high frequency upper limit of the titanium film can be greatly broadened and the power capacity is greatly improved.
(4) SFG symmetrical magnetic field magnetic circuit Titanium diaphragm is a patented technology of JBL Company. The patented technology ensures that the FB value distribution on the magnetic gap is symmetric with the upper and lower positions of the voice coil, and includes a magnetic flux balance, a structure setting for reducing the inductance of the driving source and heat conduction. Effectively suppress low frequency distortion, improve power withstand and damping characteristics.
BOSE Corporation
The company's speaker box features: the active use of the sound of the listening environment to improve and modify the radiation characteristics of the speaker, the development of a world-renowned sound field speaker box.
Bose's new technology:
(1) Direct/reflective speaker technology. Bose's speaker box uses direct/reflective technology to restore the sound of reflections from walls, ceilings and floors to the listener, using direct/reflective theory to express the level and positioning of the sound. Representative products are 901, 701 and 501 series speakers.
(2) Acoustic air flow bass technology. The technology uses the airflow generated by the "A-cousticMass" structure to couple three independent chambers to reduce the resonance of the woofer diaphragm, reduce distortion, and provide a large dynamic range.
(3) Audio waveguide technology. This technology is the research result of bose company after 14 years of research and applied for a patent. It is characterized by the installation of a long, flexing guide tube in a very small chassis structure, thereby increasing the sense of low frequency and creating a huge sense of stage space that breaks through the small box size limit.
(4) HOROFINE film technology. This thin film technology is made of bamboo pulp and wood pulp. It has perfect and balanced plasticity and rigidity. It can meet three main indicators of converting electrical signals into high-quality sound waves: low density and high Young's modulus. With a large attenuation index, it can reproduce bright, clear and very natural sounds in the mid-high range.
AR
The company is known for creating air-cushioned speaker enclosures that use acoustic suspension technology to support the woofer through a spring-like air in a closed enclosure for deep bass. This kind of speaker box has appeared since the 1950s, and it has been used for a long time.
French FOCAL Group
The company is known for creating advanced speaker units, as well as a wide range of speaker cabinets, which are sold all over the world. Some group companies have advanced speaker manufacturing technology, and they have four internationally renowned inventions.
(1) A new design called "MVF" (elimination of mechanical oscillation) system was invented. The system can overcome the shortcomings of the mechanical oscillation of the traditional cone speaker, and reduce the vibration intensity of the cone splitting to ensure high fidelity playback.
(2) In the design of diaphragm, the patented Polkevlar cone has light weight and rigidity, completely solves the problem of sound dyeing and accurate frequency response.
(3) Invented the Polyglass (polyethylene glass) treated cone, which makes the cone have high rigidity and excellent internal damping characteristics, making the sound of the unit smooth and natural, and replaying the music in detail.
(4) The newly developed diamond diaphragm in the 1990s can reproduce the gorgeous sound.
The company's speakers feature high sensitivity, and most products are above 90dB. The midrange and tweeters are coaxially mounted on the midline of the panel to produce accurate audio and video.
Danish DALI
The company attaches great importance to the audiometry of the speaker, and never uses the objective test results as the final basis. The company has a sounding jury composed of experienced and professional music professionals to make a subjective review of the sound quality of each new DALI product to ensure the unique style of DALI products.
The most notable features of DALI's speakers are: the front panel is as narrow as possible, controlling the sound diffusion angle; the box is very hard, with a surface absorbing layer device, which can effectively eliminate the resonance, stabilize the sound field, and have a stereo positioning feeling very accurate. The units used in the speakers are paired by computer test.
British speaker features
TANNOY's coaxial loudspeakers are well-known in the world, successfully solving the phase distortion problem; KEF invented the "UNI-Q" coaxial technology, which realizes the ideal of high-pitched and low-pitched coaxial sound, making stereo images accurate; QUAD specializes in The electrostatic speaker has been spared no effort to improve and develop it; Celestion and Rogers' small speakers have a 2dB bump on the test curve at 2000Hz. Some people think that this slight difference will definitely affect the tone, but the two companies The product is a representative product of the British small box, which may be the mystery of the sound of the British sound.
New flat panel speaker
Verity and NCT in the United Kingdom announced the successful development of novel ultra-thin flat panel loudspeakers in 1996, which is indeed a major breakthrough in speaker production technology.
This type of flat panel speaker has a thickness of 3mm and a thickness of no more than 25mm. The effective radiation area can be determined from 25cm2 to 100m2. Verity's NXT speakers use electromagnetic actuators, while NCT uses piezoelectric ceramic drivers. The vibrating plate is made of carbon fiber and paper, and the speaker is very light. The speaker has a wide frequency response range, which means that the angle of each character is large and the sound quality is good. The flat speaker does not need a box, and can be hung on a wall or in a ceiling like a picture. Experts predict that the application of such ultra-thin flat panel speakers is promising and will become the new generation of speakers in the 21st century.
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