In recent years, with the development of digital audio technology, the requirement of loudspeaker is more demanding. In order to adapt to the requirements of technological development and meet the needs of consumers, the world's famous loudspeaker companies are committed to improving the performance of the existing loudspeaker, and research and development of new materials, new technology and the use of new design methods for loudspeaker.
The world famous large company's loudspeaker and its system technology present situation, characteristics and unique new technology are introduced as follows:
First, the technical status quo of foreign loudspeakers and sound boxes
1. Professional speakers
It mainly refers to the loudspeaker and loudspeaker box that wait for an occasion at film, stage, hall, stadium. In recent years, with the development of new materials, new technology, new structure and new technology, the application of stereo technology and digital technology, the popularity of CD and VCD, professional loudspeaker and its system have also made great development, new products are emerging constantly. JBL, EV, Bose Corporation, USA; KEF, Tonny Company, UK; Japan Panasonic, Pioneer, Mitsubishi, TOA, YAHAMA companies, in recent years have launched a variety of professional speakers and speaker systems. Their distinctive characteristic is that the power is large, all above 200W; High efficiency, generally in 98-100dB; Directivity width. In order to achieve the above characteristics, the world famous loudspeaker manufacturers, eight immortalization across the sea, each show their magic.
The main methods adopted are as follows:
First, the use of new magnetic materials, the use of new magnetic circuit design methods. The SFG magnetic circuit design used by JBL, for example, includes new structural Settings for flux balance, reduced drive source inductance and heat conduction. The magnetic material used has a magnetic energy product of more than 3.6MgSOE. This makes the loudspeaker bear power capacity increases, replay bass strong, have strength.
Second, the use of new materials, such as the tweeter loudspeaker diaphragm using aerospace titanium material, because the titanium metal E·P is superior to the CamPro material, suitable for the manufacture of high-quality tweeter diaphragm. With the use of titanium diaphragm, the high frequency is extended greatly and the power capacity is greatly improved. The woofer uses laminated high density composite paper basin. The voice coil adopts flat wire, because the flat wire has high vacancy coefficient and high utilization rate of magnetic circuit gap, higher sensitivity can be obtained. The technology was invented by JBL and copied by other big companies.
Thirdly, a new type of horn is adopted. The exponential horn loudspeaker which has been used in professional sound amplification for a long time has been replaced by a new type of equidirectional horn. The key technology of the equidirectional bubule is that the bubule adopts side walls of different shapes. Because the simple linear and exponential formulas in the past become complex and discontinuous functions, the constant directivity can be achieved.
Fourth, the extensive use of computer CAD, CAM and CAT technology, the use of modern technology to excavate the potential of traditional loudspeaker, so that professional loudspeaker products strive for perfection. Representative products, such as JBL company MR professional speaker speaker series, SR professional speaker series.
2. AV speaker speakers
It mainly refers to the loudspeaker speakers for the sound system of the home hi-fi combination sound system, karaoke bar, dance hall and home theater. AV loudspeaker has made great development in recent years, and new products are emerging constantly. The world's major speaker companies have launched various forms of AV speaker speakers. They have not only advanced technical performance, but also technical characteristics such as practical modeling, improved sensitivity, extended dynamic range, broadened replay band and good transient response.
It is common to have two frequency divider speakers: an 8-inch or 6.5-inch mid-bass unit plus a ball-top treble unit. In order to ensure the ideal directivity and phase characteristics, the loudspeaker unit is required to have a wide range of piston vibration without segmentation vibration. Companies in accordance with the audiophile pursuit of bass effect requirements, and have developed dumbbell speaker speakers, with two 8 "or 6.5" in the middle of the bass unit sandwiched between a ball-top treble unit, designed to strengthen the bass. Three-way frequency division loudspeaker speaker box: on the basis of two-way frequency division, one medium unit is added. Its advantage is to make full use of the piston vibration frequency band of each unit, reduce distortion, and improve the power to bear the love ability.
Another significant feature of AV speakers is that they have good leak-proof magnetic properties. Magnetic circuits should be designed with magnetic shielding to ensure that video images are not affected. Today, the popular multi-dimensional stereo and home theater system is to bring the audio-visual effects of the theater to the average home, surround sound is a part of it, and a very important part.
Now the popular surround sound in the market can be roughly divided into two kinds. One is Dolby directional logic surround sound which evolved from the early "quadtrack". The other is DSP surround sound, which was first developed by Yahama. DSP surround sound is a digital processing technology to simulate the sound effects of different Spaces. This requires that the sound of front, middle and rear indicator speakers should be balanced and the directivity should be ideal. Engineers in the electroacoustic field have made unremitting efforts to improve the performance index of AV loudspeaker. By means of system design, experiment and simulation, they constantly explore the mystery of the AV loudspeaker world, and ensure that the objective parameters of loudspeaker occupy an important and necessary position on the basis of ensuring the sense of hearing.
Typical products, such as JBL's home theater speaker speaker system, include a total of seven speakers, including front main channel, middle channel, surround channel and subwoofer. The front main sound channel adopts 2 200mm bass units, 2 127mm midrange units, 1 titanium film ball top tweeter unit and horn type tweeter speaker. Use horn tweeters in movie mode. Use horn speakers for movie mode and titanium diaphragm ball top tweeters for music. The sound quality of the replay is very well designed, using multi-channel sound equalizer and 7-channel sound quality equalizer, using digital technology to create an imposing cinema sound in a small home space.
3. Heavy woofer
In the past, in order to achieve true bass output, designers have used as large a vibrator as possible. Klipsch's 27-inch subwoofer; 30 inch tapered subwoofer developed by EV. In recent years, the boom of home theater audio market promotes the research and development of large amplitude subwoofer. Typical products include: AuraSound's 18-inch subwoofer for a radial neodymium magnetic system.
A large linear range of motion was obtained by controlling the thickness of the roof and using a 0.5 inch voice coil in a 2 inch gap.
Pineer's subwooper has something unique about it. From the outside, you might think it has no overhangs, but it has something like a overhang attached to the diaphragm, which allows the diaphragm to do a long piston motion in a cylindrical frame. The subwoofer's oscillator can move back and forth up to 50px. The 6-inch woofer can reach a sound pressure level of 100dB at 50Hz, which is difficult to achieve with conventional woofers. Representative products, such as KEF company's AV1 active active subwoofer.