According to the theory of inventive problem solving (TRIZ) best device is one that is not present at all, and the task is performed. So it is with home electronics - many are not averse to minimizing its presence. This is especially true for speakers. There are many reasons. The most common of these are children who can accidentally knock over acoustics; expensive square meters eaten up by appliances; blockage of passages, etc. Well, in commercial facilities - shops, restaurants, etc. in general - a real salvation.
A concise solution in this situation are wall acoustic systems. In the view of many, these are still ordinary bookshelf speakers that are screwed onto terrible brackets. In fact, now there are a lot of wall acoustics of very different designs, different sound quality and, of course, different prices. Hope this one short review useful to get a general idea of the possibilities. First of all, this review is dedicated to design. Well, the technical nuances can be found in our Gallery.
Flat speaker systems.
As a rule, they have a rectangular shape. Among them there are very thin ones - only 2-3 centimeters thick, and there are quite voluminous ones, there are the size of a notebook, and the size of a human height. Here the main question is the sound quality and power that you need and which correspond to the size of the room. Some of the wall models sound at the radio level (who remembers), and some correspond to the High End level. In terms of finishing flat speakers, their main difference is the color of the frame and the color of the grille.
Flat models with grilled images are quite popular. In fact, they are disguised as paintings. In order for such an imitation to be complete, baguettes are sometimes ordered as tuning - from simple to luxurious. But the possibility of their use depends on the design of the columns.
Some flat acoustics should not be masked. Thanks to its high-quality finish, it can “make friends” well with many interior styles.
"Volumetric" wall acoustic systems.
The disadvantage of flat speakers is that they require a certain amount of space on the wall, and the more high level speakers, the more space they usually require. You can't go anywhere - physics. Therefore, "surround" wall-mounted speakers can be an alternative. They not only save space on the wall, but also look quite impressive.
The choice of shapes and materials is very large. But the "rule of size" is also respected. More powerful and high-quality speakers, as a rule, have large dimensions. But the "kids" should not be discounted. A well-chosen compact solution is quite capable of coping with the tasks. Typically, wall-mounted speakers work in conjunction with subwoofers. Although subwoofers are located mainly on the floor, they are not so conspicuous and not so critical to the location, although there are certain requirements here.
Among the "voluminous" wall models there are representatives of "soft" forms that can fit well into both "classics" and modern interiors. Some of them are not originally wall-mounted, but have the ability to be mounted on the wall.
There are also models built on rigid straight lines. As a rule, they are better "friends" with minimalist interiors and some areas of neoclassicism, where straight lines also predominate.
Soundbars
This type of acoustic systems is also usually placed on the walls. Mostly soundbars are used in inexpensive home theater systems. From the point of view of sound quality, it is difficult to demand anything special from them. Rather, they are designed for a very unassuming user. The design in most cases is also focused on budget modern interiors.
However, there are real "kings" among soundbars. The dimensions of such speakers exceed two meters and, in fact, completely replace full-fledged floorstanding speakers. High class end.
Finishing such systems is also different. But in most cases, you can find an option for both classics and hi-tech.
Rear speakers.
Such acoustics are used in home theaters for rear and sometimes side channels to create surround sound. In many ways, the design approaches are similar to the flat and surround speaker systems described above. The difference is that the purpose of such acoustics is quite definite - the creation of surround sound effects in a home theater. Although in some cases they are used as the main speakers in small rooms. From the point of view of "strict rules" this is not true, but for an inexperienced music lover it can be a way out in terms of design with acceptable sound quality.
Naturally, in order to achieve the optimal result by all criteria when using wall-mounted speakers, the joint work of the customer, the interior designer and specialists in such equipment is necessary. The Gallery of Faultless Electronics "Nazarov" has accumulated extensive experience in using wall-mounted acoustic systems of the most different type in a variety of interiors. Surely we will find the optimal solution for any, even the most non-standard case. Contact us, we will be happy to help you!
The review was prepared by Oleg Kostyuchenko.
I am writing this post with somewhat mixed feelings. On the one hand, the technology, about which information has appeared, is very interesting and can in many ways turn modern views in the field of its application. On the other hand, this information is more advertising than practical, since I did not manage to get direct evidence or some examples. Well, time will tell, but for now - that's what we are talking about.
Warwick Audio Technologies claims to have developed completely flat acoustic speakers (sound drivers) based on new technology. The company claims the following characteristics:
- drivers look like flat sheets of polymer, sizes vary from A5 to A3
- sheet thickness is 0.2 mm
- flexible sheets
- provided sound pressure - from 85 to 105 dB (this number, apparently, refers to measuring pressure right at the surface of the sheet)
- provide a very high directionality of sound due to the focusing of the sound wave by bending the sheet (like a curved mirror that reflects light from different directions to one point)
- extremely low current consumption, high efficiency and negligible thermal emission
- not affected by external magnetic fields
The company does not hide that their technology is a development of the ESL technology - Electro Static Loudspeaker (electrostatic sound emitter) that has already existed for several decades. ESL refers to a transducer design where sound is produced by a membrane placed in an electrostatic field. Quoting Wikipedia:
In the most common version, a high-resistance membrane is placed between two stators. applied to the membrane high voltage relative to the stators, a large amplitude signal is applied to the stators (high voltage audio signal). As a result, an alternating electrostatic field appears between the membrane and the stators, which moves the membrane. The field acts evenly on the entire membrane, and the membrane has an extremely low mass, thanks to which high characteristics are achieved: coefficient. non-linear distortion reaches 0.05%, high impulse response, flat frequency response.
Warwick Audio Technologies' technology is called FFL ("Flat Flaxible Loudspeaker"). It implements the same idea as the already long-developed electrostatic speakers - a sound wave is created by a flat membrane vibrating in an electrostatic field. However, the company's innovation lies precisely in the fact that they managed to make the structure surprisingly flexible and thin. In fact, the company has created not some kind of electromechanical design, but a completely homogeneous laminate material. The laminate sheet consists of three layers - two membranes and an insulating layer between them.
When "rocking" the upper membrane with an electrical signal, the membrane vibrates exactly in phase in all its sections, forming something similar to a piston. Thus, the sound wave generated by the movement of the membrane is very directed.
The company, of course, does not disclose more detailed details of its development.
If all this is true, then such speakers will find their application in countless places and situations: in the subway over the heads of passengers, in supermarkets right on the pictures of products, in cars, in offices and so on. and so on.
By the way, Warwick is not the only one who announced such sounders. More recently, another group of developers, this time from the Industrial Technology Research Institute, presented to the public their development in the same area - Flexspeakers. there is a video clip showing such a speaker in action. ITRI promises that their A2 size acoustic sheets will be available for sale very soon for as little as $20.
You can share your thoughts in the comments to the post.
Recently the market information technologies changed quite a lot, and not to please the end user, as we would like, but under the textbook rules of marketing. If any sector of the high-tech market noticeably lags behind the processor market or the graphics accelerator market in terms of the pace of modernization, they try to artificially create demand for it. Take at least the income of companies engaged in sales peripherals, say keyboards or simple acoustic systems. Of course, their profits are incommensurable with the hegemons of the IT world like Intel or MS, but the R&D departments of these companies do not receive funding measured in billions of dollars. That is why the introduction and development of high-tech innovations in these sectors of the information technology market (for example, wireless keyboards and flat speaker speakers) has always been so widely supported by the computer peripheral industry and raises the coveted sales levels of the respective companies.As mentioned above, companies involved in the release of simple peripherals (often these are Korean, Taiwanese and Chinese companies) cannot afford to maintain their own research centers for the development and research of new technologies. And in fact, there is not much point in maintaining such institutions, unless the company creates, say, expensive Hi-Fi or Hi-End speaker systems, because the profits from sales of speakers packed in plastic, even very skillfully, cannot be fabulous high - this is not a six hundred dollar processor with a cost price of $30. That is why the search for know-how in the field of sound systems is carried out either by independent (not related to production) research laboratories, or research centers of educational institutions, or government-sponsored defense agencies, as they say, "in their free time from the working day", in parallel with the main line of business.
One of the representatives of the last class of developers was the British defense agency DERA (Defense Evaluation and Research Agency), which, unwittingly, laid the foundation for the development of flat acoustic speakers. In fact, today, after more than a decade, it is difficult to determine the founder of the idea of "flat sound", because developments in this area were also carried out in the Soviet Union. But let's get back to DERA, more precisely to its specific employee - Ken Heron (Ken Heron), who dealt with the problem of noise reduction in military helicopters. According to him, the metal plate that forms the ceiling of the cockpit of a military helicopter created additional noise, and seemed to amplify the existing one rather than create it. Although the bureaucrats of the British defense agency did not take up the idea of replacing the panel with a plastic counterpart, Ken Heron had an idea that was later destined to be embodied in the original sound system.
Thus, in 1991, Heron's group, under the auspices of DERA, after conducting a series of additional studies, patented a new technology. However, the inertia of companies engaged in the field of sound systems made itself felt, and therefore only in the second half of the 90s was a company found that decided to make commercial investments in the further development of this certainly promising technology. That firm was Verity, which designed and sold high-end acoustic equipment, which was later renamed NXT.
NXT specialists, together with Heron's group, have come a long way in a short time, because before the arrival of the NXT team, the new speakers could only reproduce the speech range. In this way, NXT brought closer the time for commercial use of flat speaker technology. A little later, the company sells all production facilities in order to focus entirely on new developments.
So, today NXT has two technologies based on the principle of flat speakers - the flat SurfaceSound speakers themselves and the transparent speaker technology - SoundVu. The first is licensed by many companies, including such industry giants as Sony, Panasonic, Toshiba. Compaq, IBM, JVC, etc. not to mention the hundreds of others who buy off-the-shelf OEM panels to build low-cost sound systems.
The volume and depth of the lower sound range increase as the size of the display increases. The stereo effect is achieved by adding another emitter. This will make it possible in the future to abandon the speakers built into the monitor, which will reduce the dimensions of the display, as well as free up space on the table due to the rejection of the audio system. But the biggest benefit this technology will bring laptop owners who, until recently, could not boast of sound reproduction quality. The company notes that it is still difficult to say how much the cost of SoundVu-equipped PCs will increase, since the final refinement of the technology will take some time, and the appearance of real products based on it should be expected in about a year and a half. Now let's talk about the technology of flat (SurfaceSound) and transparent (SoundVu) speakers.
surface sound
What is the principle of operation of a flat speaker? A rather complex oscillatory pattern is formed on the surface of a flat radiator (Fig. 1), which creates sound, and in traditional speakers, sound frequencies of a given spectrum are generated by vibrations of the same membrane.An absolutely logical question arises: why are such difficulties needed at all? After all, a new technology, for successful use in the creation of equipment, must clearly highlight the advantages over its predecessor on several issues. A rather attractive design, with all the desire, will not be able to recoup the costs if this parameter is the only one. Of course, the primary and main task pursued by developers in creating new technology for speakers will be sound quality. Piezoelectric, electromagnetic, electrostatic and other traditional acoustic systems are not inferior in sound quality to flat speakers. A set of acoustic equipment based on SurfaceSound, manufacturers supplement with subwoofers due to the fact that flat speakers reproduce only the upper frequency range.
Fig.2. Sound field of standard speaker
Let's pay attention to the two-way radiation pattern (Fig. 2) of flat speakers. In traditional acoustic equipment, it has a different form, namely, in contrast to this one, it is rather narrow and far from spherical, which leads to a limitation of the stereo effect perception area. So in this matter, flat speakers obviously win. Also a reflection sound waves from the walls of the room is quite good. So, an attractive design, surround sound, of course, cannot be put against low-quality sound, but we'll wait and see.
SoundVu
SoundVu is a technology that is supposed to transform the glass of computer monitors and the plastic of mobile and mobile LCDs. desktop computers into the loudspeaker. In fact, SoundVU is an evolution of SurfaceSound, with the only difference being that the former will make flexible, transparent, almost colorless plates sound. SoundVu solves the problem of converting a transparent surface (such as a computer monitor) into a loudspeaker. In practice, this is very convenient, because for most owners mobile phones, the hole for the speaker and the most polluted place on the phone have long become synonymous. The use of new technology will solve the "hygienic" problems of using mobile phones. In addition, the use of SoundVU will reduce the body of cellular devices even more, which means it will increase the attractiveness of the latter. SoundVu, according to John Visor, director of NXT, turns a computer or television screen into a loudspeaker with full dynamic and frequency range. The larger the screen size, the louder sound and "deeper" bass. To create a stereo sound, it is enough to build two transducers into the screen.Flat "touch" speakers for mobile phones manufactured by Matsushita Electronic
Matsushita Electric has introduced a new narrow speaker - Sound Slim, which uses magnetic flux created in the horizontal direction by two repulsive magnets. In addition, the company did not stop there and now presented new fruits of its researchers using the so-called Sound Window technology: these are the Acoustic Panel - a flat overlay speaker, and the Acoustic Touch Panel (A-TTP) - a speaker integrated into the touch panel.
The essence of the technology lies in the fact that for the manufacture of speakers using Aero Drive technology, a thin film is used that does not require a solid base to create vibrations in the sound range. Moreover, according to Matsushita, external pressure on some part of such a panel will only lead to a loss in volume level, since the remaining areas of the elastic film will continue to vibrate.
Everyone knows that the holes in the current cell phones and PDAs, through which the sound "leaks", are places of maximum accumulation of dirt and moisture. The idea of combining the speakers with the protective panels of LCD screens is quite promising, as it will help to get rid of unnecessary holes in the pocket PC / mobile phone completely. Matsushita Electric intends to start shipping samples of these speakers in August, and mass production of acoustic panels will begin in March 2003.
Overview of speakers based on flat sound technology
Jazz Hipster Monaco
Sleek, flat speakers that are only 13mm deep and the membrane is a 3mm thick plate. This Monaco speaker system, which consists of three components: a subwoofer and satellites, has a power of both systems - 500W. The frequency range of the Jazz Hipster Monaco model is - and 80 Hz - 20 kHz. When listening to this model, one can distinguish fairly clean high frequencies and good, although not ideal, mids. But in general, the sound quality is decent, it allows you to use this model both for listening to music and for computer games, due to the presence in the kit, as mentioned above, of a subwoofer. The low-frequency unit produces 80 Hz, of course, this parameter will not satisfy a strict connoisseur of music, but as for computer speakers indicator is very good. Organic lines plus good technical indicators allow us to state with confidence that these speakers, made on the basis of SurfaceSound technology, if they do not replace traditional ones, then they will definitely. Jazz Hipster Malibu
These speakers, developed by Jazz Hipster Corporation, are simpler than the previous ones, if only because they do not include a subwoofer, that is, if you want to listen to a rock song or shoot some computer toy, you will have to "fork out" for a separate subwoofer , which has a slot in this model. The speakers are called Malibu. The declared power is 320W, and the frequency range is 200 Hz - 20 kHz. Of course, you should not believe any of these figures measured in incomprehensible parrots, but simply evaluate the sound quality. When listening, the impression is ambiguous, of course, on the one hand, the sound is quite clear, but the bass of this speaker system is very bad. All the same, 200 Hz cannot provide decent low frequencies with all the desire. And now about the main thing - about the price! Approximately the speakers are quite affordable for users - only $30, the previous Monaco model with a subwoofer and a much better frequency range, and, accordingly, high-quality sound - $35. Genius SW-2.1 Slim
The name of these ultra-slim A-626 speakers is based on NXT SurfaceSound Technology from NXT New Transducers Limited. In this model, the sound source is a flat solid surface. Testing this speaker system, which has the designation SW-2.1 Slim in the Genius line, we can conclude the following: low frequencies this model imperfect, but it should be noted, due to the presence of a subwoofer, the sound is quite good compared to, say, Malibu speakers manufactured by Jazz Hipster Corporation. The design and ergonomics of the A-626 are standard, that is, without any special differences from existing prototypes based on SurfaceSound technology. Particularly upsetting is the standard coloring - milky-colored plastic that is boring to hell. The power of the satellites is 2 watts, and the subwoofer is 6 watts. At high and medium frequencies, the acoustic characteristics of the A-626 are quite good - the sound is rich and of high quality. These speakers are very similar to the previously reviewed Monaco models in many ways, such as: dimensions, ergonomics, frequency range and the actual price - $30. Benwin DML 2000A
Consider a speaker system based on Benwin DML 2000A SurfaceSound technology. The presented set of flat speakers consists of two actually flat speakers and a subwoofer. Appearance this model is quite stylish and will "fit" well not only into the interior of an office or cabinet, but also fits perfectly, meaning the speakers themselves without a subwoofer, if not directly butt to a laptop, then certainly in a briefcase for it. It is worth noting that Benwin products have already presented a similar BW2000A speaker system to the court of users, which they declared to the world, and more specifically to competitors in this area, that this sound technology is of interest not only limited quantity manufacturers. So, now about the quality of the model. When listening to music at different frequencies, we can conclude that, as inoffensive as it is, the reproduction is imperfect. That is, at low frequencies, the sound quality is in principle comparable to standard counterparts in terms of price, but medium and high frequencies are not without sin. When listening to rock compositions, interference is observed, in the form of rattling, and when using these speakers for computer toys, the sound, although quite clear, is not saturated. But there is no evil without good. The stereo effect of these speakers is perhaps an order of magnitude higher than, say, standard models, that is, the sound is voluminous and the reflection of sound waves is excellent. TEAC PowerPanel-300
Can you call the speakers of the TEAC PowerPanel-300 speaker system ultra-thin? Of course yes. With such speakers, as they say, wherever you want, admire at home, and if necessary, along with a laptop, which is especially nice, on the road. And they take up little space and the sound is decent. The hard surface of the speakers, the vibration of which is carried out by means of a transducer, not only inspires peace of mind during transportation or other accidental physical impact, but also provides good sound quality over the entire frequency range. Testing has shown that in view of, of course, the presence of a well-designed subwoofer, the acoustic characteristics of the sound are especially distinguished by purity and realism at low frequencies, although, as mentioned above, mids and highs are normal. I will make a reservation that such a conclusion was made mostly in comparison with other speakers based on flat technology, because the standard analogues, although not so "extravagant", have no complaints about the quality of reproduced sounds, well, or almost none. Let's return to the considered model. Satellites have a depth of approximately 13 mm, which has a good effect on the stereo effect of this speaker system, and the working (sounding) surface has dimensions of 140 mm by 124 mm. It should be noted that there are also disadvantages, such as the small dimensions of the subwoofer, which lead to a deterioration in the sound quality of classical music and the bass is somewhat worse. In general, this model, in my opinion, can compete quite well with existing analogues. XS-iV S80
Another model based on Surface Sound technology. Appearance, ergonomics leave the most positive impressions, but there are some comments that should be highlighted. Firstly, the use of an elongated, undeniably attractive design, entailed some difficulties, for example, in the area of compactness of the speaker system with a laptop. Secondly, it is necessary to carefully place this model, for example, on a desktop, in order to avoid falling due to the small area of \u200b\u200bthe base of the speakers, but still, they look elegant. The delivery set is standard, that is, two speakers of 7.5 W each plus a subwoofer - 24 W. The quality of the reproduced sound at low, medium and high frequencies can be defined as standard for of this type equipment, that is, not bad, but could be better. But the stereo effect is really incomparable. With increasing frequency, the narrowing of the sound field is practically not noticed, which is typical for a dynamic head with a traditional piston operation scheme. If you really know a lot about acoustics, then this "flat" speaker model XS-iV S80 from the manufacturer TDK Recording Media Europe is just what you need, and if you need excellent sound quality, then you should think about it. Conclusion
To date, the growth prospects for the development of the market associated with the reproduction of sound are very high, which, in fact, is evidenced by the large abundance of such goods. Indeed, such achievements as reduction in size, significant improvement in ergonomics, more realistic acoustics of the model, etc. will lead to new technological solutions, which will increase, coupled with the above advantages, and such an important indicator as sound quality. Flat and transparent speakers, I think, are those first steps towards beautiful and decent-sounding equipment. Well, - let's wait and "listen"!While our industry was setting up the production of Electronics 100AC, progress in the West did not stand still, new speakers were being introduced with coaxial, isodynamic, electrostatic loudspeakers. The largest Japanese corporations - Sony, and then Matsushita (Technics), began to develop completely new dynamic heads operating in a piston mode. Basic distinctive feature These drivers were completely flat rather than honeycomb cones. A flat radiating surface has no resonances inherent in cones, no stress zones, and is itself phase-linear and closer in nature to musical instruments.
Already in 1978, Sony introduced the prototype of the most high-tech speaker system in the world - the Sony / Esprit APM-8. The diffusers of all four speakers are square in shape, the low-frequency one had as many as 4 cobalt, core powerful magnetic systems that moved a single flat diffuser like a piston. Then, a deep bass of 25 Hz, which was not reproducible by any speaker, was reached at a level of 8 dB, and to this day an unattainably small THD in the low-frequency region, which even at 40 Hz does not exceed 2%!
Sony/EspritAPM-8 (1978)4 lanes, multi-amping capability, anti-diffraction coating, 102kg. 500W. 25-30 000Hz.
Inexpensive but high quality flat honeycomb radiatorTechnics. (used in the Technics SB-7 model)
TechnicsSB-10 isodynamic HF emitter, cellular midrange with "invisible" suspension, honeycomb bass (32cm) with coil extra large diameter (160mm). The magnet and two centering washers are inside this reel! It looks like the speaker is inside out. Such a complex design was produced only by Technics and for that short time.
The Lo-D company (Hitachi concern) did not follow the path of Sony and Technics and developed its own flat diaphragms, but not of a honeycomb design, but filled with synthetic foam and a velvet acrylic coating of the radiating surface, the same Lo-D diaphragms were used to make passive radiators.
Trio (a division of Kenwood that produces high-end audio equipment) used cone bass drivers reinforced with honeycomb stiffeners. Acoustic design served as a special horn phase inverter, occupying the entire back AS. Trio produced mid/high frequencies with flat carbon fiber diaphragms impregnated with acrylic resins.
JVC in its speakers (Victor Zero-7) has developed cones entirely from foam-resin composition. In the design of the speakers, the suspension was fixed on the back side and was "invisible". The innovation was that the reflections of sound waves disappeared from the edge of the suspension, which in the standard design return back to the diffuser. The three bands of such speakers were complemented by an ultra-light ribbon super tweeter with an acoustic lens.
Lo-D HS-5000 (Hitachi's Lo-D Division Specializing in High-End Vehicles)
flat radiatorLO- D, diffuser filled with special foam and laminated with metal.
The company's flagship model Technics- SB-M 1 (1981) 4 lanes, honeycomb radiators - a kind of Sony / Esprit APM-8 answer, only more than half the price .
The honeycomb filling of the diffuser gives incredible rigidity with the highest coefficient of internaldamping, while having a low mass.
Trio LS-1000, back panelis a mouthpiece thatinteractswith roomfor listening what raisesreturn of the mostlow frequencies.
OnkyoScepter-300, the rear panel with the appearance of a conventional speaker has 6 multidirectional mid-high frequenciesemitters, which, according to the developers, gives a feeling of a complete 3-dimensional picture of the sound image.
VictorZero-7. Due to the use of flat radiators, even in a multi-band design, a minimum phase correction is sufficient.
Diatone DS-505, 4 bands, cone woofers - honeycomb design, domed - super light titanium-boron.
At the turn of the 70s-80s, after lengthy experiments and research, many designers came to the conclusion that the ideal radiator is a point source of sound. With such a loudspeaker, phase and transient distortions are minimized, the sound is emitted from one point without spacing the bandpass speakers (LF, MF, HF) in space. What gives the listener the feeling of full presence at the concert, the sound is not tied to the speakers, and all virtual sources are accurately localized in space. Wideband dynamic heads are not able to reproduce the entire audible frequency range well, especially in the high-frequency part. Therefore, the developers began to install several loudspeakers on the same axis. The most interesting solutions were used by Tannoy and Altec Lansing.
Tannoy used large paper woofers with an acoustically transparent dust cap and a conical hole in the core through which the tweeter radiated, mounted inside the woofer's magnetic system and operating from its magnetic field. The main disadvantage of this concept is the oscillation of the low-frequency diffuser, which simultaneously serves as a mouthpiece for high frequencies.
TANNOY Autograph (K3808) (1979) are designed specifically to be placed in the corner of a room. acousticdesign - the front part of the speaker is loaded on the horn, the back part on the labyrinth of a complexforms.
coaxial speakerTannoy. The dome tweeter is located inside the cone woofer and uses its own magnetic field only on the other side of the magnetic system.
Altec Lansing 620B Monitor, 1978The tweeter is attached to the back of a large 15" woofer and radiates through a hole in thehis core to his own mouthpiece.
It was only towards the end of the 1980s that Technics was able to fully embody the point radiator theory in their SB-RX series speakers. In addition, the Technics point emitter worked in a piston mode and was completely flat.
I would like to note one more significant idea of the turn of the 70-80s. This is a mechanical feedback system (EMOS) developed by Philips. Everyone knows that amplifiers with a high output impedance reproduce the midrange and high frequencies of a musical signal very vividly and naturally, and amplifiers with a low output impedance (which causes a high damper factor) play the bass well and accurately. Philips engineers have placed a micro sensor on the woofer cone that monitors amplitude, temperature, power and other parameters. The data is then sent to a microprocessor that controls an amplifier installed in the speaker cabinet. Based on the information received, the microprocessor regulates the output impedance of the amplifier. When implementing multiband amplification, the design is freed from passive crossovers, in which part of the signal is lost. It becomes possible to change the parameters of the amplifier, as it is necessary in this moment time.
Installing regular rear speakers
Rear speakers give the owners a lot of "headache". If they are placed on original or non-branded stands, then they begin to interfere with free passage to the sofa, often injure the owners with the sharp corners of the cases, the cables from them get in the way under their feet. The center of mass of the column-stand duet is located on top, which clearly does not add stability to them. Backfill stands for rear acoustics are very rare and even less often covered with sand or shot.
Suspension of traditional rear speakers is also a problem. If you mount the speakers on the wall with brackets, the resulting depth of such a design is in the region of 30 - 40 centimeters, they simply “stick out” and obviously do not decorate the interior with their appearance.
In order not to hit the rear speakers with your head, they are suspended at a height of 1.7 - 2.0 meters from the floor level. The wall-mounted speakers are much higher than the front speakers, and the resulting sound image at the back is “pulled up”. The 3-D sound effects intended by the director are distorted.
Flat acoustics HECO Music Style Rear 200 F and its advantages
Flat wall acoustics not so long ago appeared in model lines HECO, closes a lot of technological and aesthetic issues.
Flat acoustics does not spoil the interior at all and looks more like not an acoustic system, but a kind of furniture element. Fortified close to the wall, it protrudes a minimum distance of 10 - 11 cm, it is almost impossible to touch it.
Installed at the height of the ears of a sitting person (110 - 150 cm from the floor level), the HECO Music Style Rear 200 F flat wall acoustics together with the front speakers creates a perfectly even sound image in the horizontal plane.
By hanging minimally protruding speakers on the wall, even in the amount of 4 - 6 pieces, you can create a full-fledged home theater with 7-9 rear channels in the latest Dolby Atmos or Auro-3D surround sound formats. At the same time, this multi-speaker audio system will not cause any damage to the interior.
The second area of application of wall speakers is the acquisition of a high-quality audio system for secondary rooms in the house: dining rooms, kitchens, children's rooms and bedrooms.
Installed on both sides of a hanging TV, the HECO Music Style Rear 200 F wall speakers create an excellent stereo sound picture, take up almost no space and look very organic.
In the dining room, kitchen or nursery, the use of full-sized floorstanding speakers is often inappropriate, and owners have to listen to the sound quality coming from the speakers built into flat-panel TVs. High-quality wall-mounted speakers mounted on both sides of the TV work ten times better than internal speakers, even from a native TV amplifier.
P.S. Flat acoustics HECO Music Style Rear 200 F is a high-quality product with a natural, reference transparent sound in the vocal range. Buying these rear speakers, you will never regret the money spent on them.