Acoustic systems for home theaters: specifications, principles of adjustment, options for the location of the components indoors.
The high-end material of the column body largely contributes to their maximum natural sound.
Compact speakers are commonly used in small rooms
Embedded loudspeakers are used if there is no place for ordinary acoustics
For lovers of comfort, the aesthetic appeal of the columns is no less important than their high-quality sound
A new word in the design of loudspeakers for home theater-electrostatic emitters (view from the rehalar and facades). Despite the "transparency" - they sound more than convincing
As practice shows, voice the "naked" room with a minimum number of furniture is not easy for the installer, this is a serious task.
Case without a phase inverter, wood chestnut, powerful 254 mm speakers - All this helps to reliably reproduce the sound pattern
Sometimes it is convenient to purchase a set of acoustics together with all electronic components.
"Aged" columns in the company with a lamp amplifier look spectacular
The task of all subwoofers is the same, to accurately reproduce the lower bass
Si series inklocks used high-tech multi-layer diffusers like "Sandwich" (Audio Vector)
Outdoor speakers KVK 7 (Davis Acoustics, France) is characterized by a high sensitivity - 93DB
Loudspeaker housings are often performed with natural wood trim
For dumping the rear, dipole acoustics are used with two speaker sets. Their advantage is the non-directional "surrounding" sound
The acoustic system C3LTD from PIEGA (Switzerland) is equipped with a polished aluminum housing
Compact rear column is attached on the brackets
Accurate reproduction of musical images - a complex task "with many unknowns". The performance is influenced by the technical characteristics of acoustics and electronic components, the location of sound sources, the acoustic parameters of the room for listening and other factors. Ot, how to balance all these "unknowns" will be discussed in our article.
Acoustics is proudly
To reproduce sounds in home theaters, acoustic systems (AC) are used. They consist of one or more sound emitters (speakers, loudspeakers), an electronic device designed to separate signals reproduced by different speakers (crossover), and housing. Home theater Complex can enter up to eight AU (central channel, front and rear speakers, subwoofer), differing in their acoustic parameters, the number of speakers, body design and other characteristics.Among the acoustic characteristics, the most "in demand" are the following: range of reproducible frequencies, sensitivity, harmonic distortion coefficient, power, amount of speakers, materials from which speakers are made, the presence of magnetic protection and type of loudspeaker.
The frequency range indicates the coverage of low and high tones that can play the device. Loudspeakers are considered to be the best, the closer their "working" range to parameters 20-20000Hz. It is believed that these tones perceives the "perfect" human ear. The time of the audio range is usually. However, there is a sound in mind without clearly audible distortion. To actually reproduce it without distortion within these limits, only very few Hi-End-class speakers are capable of. But companies are often cunning, indicating as a "working" maximum possible range of frequencies reproducible by their acoustics. More accurately, the real range of reproducible frequencies can be judged by the amplitude-frequency characteristic (ACH). This is a graph of the dependence of the magnitude of the amplitude of the sound signal from its frequency. Occupation of the acoustic system is evidenced by a uniform curve, without "peaks" and "Vpadin". The nominal range of high-quality ACs, the non-uniformity of the Chart of the ACH is 2 DB and less; The non-uniformity of ACH over 8DB is estimated as mediocre.
The dynamic range of acoustic systems is the ratio of the maximum sound pressure generated by them to minimal. A wide dynamic range is particularly necessary for correct reproduction of records, in which the volume level is strongly changing, for example, when a cascade of deafening explosions should be strongly changing the heroes. The system with a dynamic range over 90DB is considered quality.
The harmonic coefficient in percentage calculus indicates the range of distortion by the loudspeaker of the simplest signal (addition of harmonics), the tone of a certain frequency (usually 1000 Hz). Pension columns The value of the harmonic coefficient must be less than 1%.
The sensitivity is the level of middle sound pressure developed by the acoustic system when the signal is supplied to 1W at a distance of 1 m from the loudspeaker. The sensitivity of more than 90DB / W / m is considered high, low-less than 85DB / W / m.
The capacity is a very cunning indicator, since there are several types of its varieties. Typically distinguish the power rating (recommended by the manufacturer when the columns will operate in a given range of distortion, not exceeding it) and the maximum, in which the speaker is able to function a certain time (maximum minute) without critical changes (and after this time it may even collapse).
How sensible to choose acoustics, based on its "tactical and technical" characteristics? An experienced professional is able to tell about many things, although it is, of course, psychological preferences are peculiar. Hooked, the man inexperienced can simply get confused in numbers. The same range of reproducible frequencies on paper will look very solid, but in reality it will be, for example, that the system with a narrower range of reproducible frequencies "plays music" is much better. After all, according to many music lovers, bringing additional distortion from acoustics into the sound of additional distortion from the side of acoustics is much worse than, say, a lack of range of reproducible frequencies. Therefore, you should not try to determine the quality of acoustics according to its passport data. Only listening can be able to give a certain answer as well as the selected technique.
The last century for assessing the quality of sound-reproducing equipment was actively used by very capacious, but "dimensionless" term "high loyalty of sound playback". For now, this term, unfortunately, is forgotten, it is found only in the form of Hi-Fi abbreviation (High Fidelity). Alas, the accuracy of reproduction of sound shades of a particular musical product can be measured only by a person. The content of the "live" sound track is difficult to formalize, it is impossible to calculate on the computer- require a high-class specialist. After all, the technique may sound clean, in detail, have a wide range of frequencies, but do not reproduce the content of musical images conceived by the author. ONE SOUNDTRAK TO THE FILM TRANSFER EVERYTHING only in the set of "correct" noise.
Opinion of a specialist
Listening must be carried out only with licensed media. Later, by having already bought acoustics, you can deliver a license and pirate disk and feel a colossal difference. Choosing acoustics for your home theater, be sure to listen to the store / cabin three or four sets that suit you at the price, recommended by the sellers (the seller of a specialized store should approximately define your preferences on the primary conversation) and, of course, are suitable for design. Do not forget about this important moment. The aesthetic perception of acoustics can sometimes be when choosing a system in the first place. Preparing for watching your favorite film, you are fully relaxing, adjusting to rest. Accordingly, the appearance of the home theater zone should cause you a feeling of comfort and all sorts of positive emotions. I am glad that today very many manufacturers began to pay increased attention to the design, finishing their acoustic systems. Some of the real works of art!
Zhanna Zhulay, PR manager of the company "Russian game"
Loudspeakers: Zries in the root!
Most often, cabinet acoustics are used for sounding a home theater (DC), that is, floor or shelf columns (differ in size and mass). The column housings can be either completely closed or equipped with a phase inverter-hole of a certain size and shape. The phase inverter allows reproduction of lower frequency signals, but, like any additional part, complicating the design can reduce the overall sound quality.
"Classic" body column-box from chipboard, MDF or plywood, trimmed with veneer. Some Hi-End models are made of valuable wood rocks (so, SS21 AC from Nakamichi, Japan, are made using a rosewood). Along with wood, materials such as plastic, fiberboard, aluminum are used (the most common view among the design speakers: Fresco from Martin Logan, USA; Alu Series from Magnat, Germany; A7 from Jamo, Denmark), Glass (Waterfall, Germany), plus Their combinations (SIGNO from Quadral, Germany).
The loudspeakers of the "traditional" aux are devices of an electrodynamic principle of operation. They consist of a housing (diffuser), diffuser, sound coil and magnet. The coil is connected to the output of the power amplifier, which creates a current of the audio signal in it. When interacting with the magnetic field of magnet magnet, the coil comes into motion, as well as the diffuser fixed on it, which is the element emitting the sound. This design is tested by time and allows you to get high quality sound. But in recent years there have been many new acoustic systems arranged in a different principle.
We mean the so-called electrostatic emitters (the leader in their production is Martin Logan). The sound source is a thin mobile membrane, which provides accurate and clean sound in a wide range due to its low mass and large area. No diffusers are sometimes used to play high frequencies, and loudspeakers in which a thin metallized tape is installed as a diaphragm. Embedded acoustics appeared and widely applied. It is released by SPEAKERCRAFT and RUSSOUND (BW and KEF (United Kingdom), Jamo, Mirage (Canada), Martin Logan and other manufacturers. Embedded acoustics can significantly simplify the problem of placement of loudspeakers in the room. But such "speakers" is already simply so out of place in place you will not move.
Location of home theater components:
(five speakers and subwoofer);
(added "Central Rear");
(two central rear loudspeakers);
Choosing a set of acoustics, one should prepare for its methodical listening. At the same time, the most important thing is not to hurry. Some sellers offer to listen to specially selected segments of records, which are distinguished by the perfectly verified "sound scene" and beautiful colors. The spectacular entry when the listened is perceived as the advantage of the speakers. In fact, it is necessary to "check" all the styles that are planned to listen to the acquired acoustics. If the buyer is going to listen to pop music, it makes no sense to check acoustics using classic or jazz records, and if he wants to watch a movie, let it take with me favorite DVDs.
We must still draw your attention to what makes sense to listen to the acoustics, stood in the "His" room at least 60-70 hours. If the seller, for example, says: "Yes, we have just what you want, but in stock. Wait, now I will bring, install and listen," - never agree! We lose a lot of time and do not get due results (most likely, the acoustic system will manifest itself from the best side).
How much should the potential buyer of acoustics for home theater? As practice shows, the costs of it are 30-60% of the means spent on the technical components (not including the display means). By purchasing loudspeakers, do not forget about the cable used to connect them. A good cable is very silent, the costs of it make up about a quarter of the cost of loudspeakers.
Opinion of a specialist
Why is high-quality and reliable technician fails? Often, due to improper, careless operation. Exclusive columns (and other technique of Hi-End) are developed taking into account the mandatory careful circulation. In order for the equipment that stands for many thousands of dollars, overload, use in a strongly smoked, dusty room, to carry out the columns with paper diffusers, decorated with expensive rocks of the tree to the wedding dance floor in order to sweep the public, does not fit the manufacturers in the head.
Mikhail Shirshov, HI-FI Technology Manager Company M. VIDEO"
"Underwater stones" acoustics
The options are an important, but not defining factor, since during the repair process they can be very significant. Therefore, experienced specialists recommend starting not from the premises, but with clarification, so to speak, "human factor". After all, the composition of the family, age, the usual rhythm of the life of households to adjust much more difficult. Also, when choosing an acoustic system, it is important to take into account the frequency of reception of guests, love for listening "just music" and other habits of the inhabitants of the apartment.It should also be remembered that the columns are the most vulnerable element of the home theater. They often fail against overloads. Curious paradox: spoil high-quality columns much easier than the amplifier with a weak output signal than powerful. The cunning of a weak amplifier is manifested at the time of universal fun, when the owners require a loud sound. At maximum power, the amplifier contributes strong distortion into the signal. These "jumps" are much more dangerous for the columns (especially for high-frequency speakers), rather than an intense signal, but without distortion supplied from a powerful amplifier. Therefore, the power of acoustics must correspond to the power declared in the passport of the amplifier. In contrast, it is necessary to remember that it cannot be turned on at full volume.
Regarding the design of the columns, one very simple rule cannot be forgotten: the simpler, the better. If you will be offered for approximately the same money in the store to your attention - one "classic" design (two speakers, a rectangular body), the other three-four low-frequency diffuser, a rupore high-frequency speaker, a cunning slit slicer phase inhentor, the likelihood that It was good, in the first case above, because in the second task that stood in front of designers and developers was much more complex.
Opinion of a specialist
To voicing the home theater, in no case is it not recommended to use less than high quality loudspeakers than those that are used to listen to music, just because it is "movies". Even a simple dialogue of actors (not music, not special effects!) With the help of high-quality acoustics, magically transformed.
Alexander Klyachin, Audio Developer
Adjuster caused?
The most "thin" part of the procedure is to adjust the speaker system of the home theater. However, the solution to this problem is increasingly charged with electronics, more precisely, a special automatic configuration program. Externally, it looks like this. Caudovideoresivera (the device responsible for decoding the audio signal and its gain) of a fully assembled home theater connects the microphone located in the center of the room (where the audience will be subsequently), and a series of specific signals are transmitted via speakers. The receiver using the microphone "listens" all loudspeakers and reconfigures the parameters of the audio signal for each of them, adjusting the timbre, volume, signal delay time for each channel.
Receivers are suitable for analysis and signal processing, properly equipped. Initially, such devices ("sound processors") were offered only by Meridian (United Kingdom) and was very expensive. However, today are similar, but cheaper systems are made by Japanese companies Sony, Pioneer, Panasonic, Yamaha. Daily receiver models worth more than $ 1000 The presence of a built-in audio processor is considered already "the rule of good tone" (there are samples of Hi-end techniques that are not equipped with a processor, they are supposed to be configured solely manually). There are configurable subwoofers produced by Velodyne (USA) with a built-in eight-vapor equalizer, an analyzer of the ACH spectrum and a microphone. There are also special test and configuration discs, on which fragments are selected, the bright characteristic moments of which help "catch" the desired sound tone.
Inclusive Alternatives to the complex and painstaking selection of equipment are offered "cinemas in one box" - systems that are fully equipped with the necessary equipment and ready for "immediate" connection. The composition includes a set of acoustics (usually five loudspeakers plus a subwoofer), a receiver and a DVD player. Since all components are issued and collected by one manufacturer, their best combination and clear interaction are ensured. Accordingly, the appearance of such a home theater is designed in a single stylistic key. At the same time, such systems may differ quite high power at a relatively small price. Thus, the LH-T1000 cinema from LG at a cost of about $ 400 is designed for a room with an area of approximately 30m2. More details we will tell about the finished sets of home theaters in one of the following articles.
If we talk about an acoustics-oriented consumer-oriented segment, then the sets worth up to $ 500- 1500 are rarely universal. Someone likes loud dynamic music, someone muffled, calm, relaxing. If a set of universal acoustics is required, equally well coping with any task, its cost can be higher.
An example of a sound absorption system for DC ("architectural electronics"):
| A- location of the panels on the ceiling; |
| Base the panels on the walls; |
| the design of the floor covering; |
| G-diagram of the location of acoustics and other objects |
| Cost of materials | $ 12000. |
| Processing work | $ 3000. |
| Chief installation | $ 300. |
| TOTAL | $ 15300. |
Air instead of wires
Cable connections of components are used in most audio systems for home theaters. The cables unfolded on the floor are little decorate the room, so the sets of loudspeakers with wireless transmission of data on the radio channel are becoming increasingly popular. There are both fully wireless speaker systems (DA-W6100, LG, Korea) and with wireless connection of only rear channels (DCS-515 from Pioneer, SoundSpace 12mkii from Nakamichi). Wireless acoustics, of course, is very convenient, as the loudspeakers can be installed or move from place to place without any problems. However, the transmission of data on the radio channel always leads to a deterioration in the quality of the signal, therefore, in the HI-END technique, this method does not apply.Another way to simplify an enchanted cable design of home theater is to purchase a so-called reflected sound system. Twin used front acoustic systems equipped with numerous speakers. Sound waves from them, reflected from the walls and the ceiling, create a three-dimensional surround sound. Reflected sound systems are used in DCS-323 home theater kits (Pioneer) and HT-DS460 (Samsung, Korea). The more speakers, the higher the sound quality - in the YSP-1 model (yamaha) of them 42, and in the "sound projector" PDSP-1 (Pioneer) already have 254. True, the price of such a panel is $ 40000 (the cost of YSP-1 - $ 1500).
Walls that are beautiful
Music lovers are well known how important the acoustic features of the room in which the entries are being listened to. The room itself acts as a certain equalizer, amplifying sound at one frequency and muffling on another. At the same time, it is known that in the placement of the wrong form (non-commercial in the plan, with non-parallel walls, a broken ceiling line) sound quality is usually higher. On the contrary, the most "severe case" can be considered the room of a cubic form, in it strong sound distortions are almost inevitable.
Since indirectly in terms of premises in apartment buildings are rare, a rectangular room with a size ratio of 1: 1.3: 1.7 (height, width, length) is best suited for home the cinema. If necessary, the dimensions of the room can be corrected using mounted ceilings or drywall wall panels, but at the same time the resonance of plasterboard panels in low frequencies occurs. The ATU, in turn, can lead to a deterioration in the sound of acoustics in the field of low frequencies (weakened bass).
In general, the correct reproduction of bass is most dependent on the properties of the room. For example, according to acoustic calculations, the room in which the bass tone of 50 Hz is well reproduced, should have a volume of 320m3 with a ceiling height 5.4 m. Of course, at home about such "parses" you can only dream. (However, in consolation, we note that the dependence of high-quality reproduction of low frequencies from the size of the room is non-linear in nature, for bass tones with a frequency of 100 Hz is enough room with a volume of 40m3). Therefore, acoustics at the design of small rooms use various tricks. For example, special ceiling structures designed to effectively reflect bass tones (note that, improving the acoustics of the room, you are far from always simultaneously improve its appearance).
Acoustic treatment of the room begins with the calculation of its parameters. Today there are many special computer programs that can be carried out with a more or less detailed acoustic analysis of the room (for example, taking into account not only its geometry, but also the location of the furniture), as well as obtain recommendations for the location of sound sources, visitor sites, materials for finishing Paul, walls and ceiling. The program also will also "report", what frequency of tone may have to be artificially jammed or, on the contrary, to increase using the equalizer and what surfaces should be rebuilt. If there is some experience and a powerful computer, an approximate calculation can be made independently. But to achieve a really high-quality result, it is better to still seek help from professional installers. A comprehensive study of the premises by specialists will cost about 10% of the cost of equipment (approximately $ 1000).
The main article of the costs of acoustic treatment of premises belongs to the materials that are fairly expensive. Warely cases of occupational acoustic processing of the premises of its walls are trimmed with the panels of the Swedish company Ecophon. Among the soundproofing and sound-absorbing materials, it is also worth noting the mineral wool slabs "Shumanet-BM" ("Acoustic Materials and Technologies", Russia) and Wilhelmi Acoustic Panels (Germany). However, in order to drown out the room, sometimes it can be drizzled with carpets, sitting on the floor of the Palace and use soft plush furniture as seating places. At the same time, it must be remembered that the requirements for acoustic processing of the premises of the concert hall and the cinema radically differ (mainly due to the different nature of the sound received). Wheel "Live Sound" is characterized by a relatively small volume, so it does not need to be mad, which sometimes you can not say about the sound of a powerful acoustics of the home theater. Another sometimes encountered error - "airborne" rooms (too many sound-absorbing materials are used in their finish). Plush rooms The sound "As in a clean field" is not perceived very comfortable, acoustics sounds localized, dryly, and a holistic sound picture may not work out.
The arrangement of loudspeakers for home theater is carried out according to certain rules. The front speakers and the viewer in the plan must be in the tops of an equilibried triangle. In the height of the column, as a rule, placed on the same level with the "line of the ears", but in some cases they can be installed above or lower. The altitude of the placement affects the timbre color of the sound and the height of the sound scene. Similarly, the sound is changed depending on the distance from the loudspeakers to the wall. The closer they are located to each other, the more emphasized the bass. In addition cases, it improves the sound picture (especially with relatively low-power loudspeakers), but often the oversaturated bass is perceived as an unnatural, distorted "Bubnej". Auto for each column there are certain recommendations regarding the distance from it to the wall. Let's say, Martin Logan relends rely on 60cm from the wall.
The central loudspeaker is placed as close as possible to the cinema screen (after all, the image of the heroes and the dialogues for which the central channel corresponds to, should be perceived as a single integer). Frontal loudspeakers nominate a few forward relative to the center and take a little deposit in his direction, so that all of them are located on the arc of the circle, in the center of which is the audience.
Rear speaker systems are often located on 40-60 cm above the head of the viewer. They are tasked - to emphasize the surround effect of the sound picture. The angle of rotation of these elements is selected by the configuration after installation, during the system debugging system. The most difficult thing to find the "right" place for a subwoofer. Often it turns out empirically: the specialist simply moves the subwoofer from the place in place and defines the desired point, based on the quality of the sound.
If we want to recall once again that the selection of an acoustic system is the process of a long and painstaking, requiring certain experience requiring from the owners. It is not by chance that many music lovers are capable of "sorting out" dozens of acoustics kits, in turn setting them at home to assess the quality of the sound. In many cases, only the method of "samples and errors" allows you to achieve the desired result.
The editorial board thanks the company "Architectural electronics", "M. Video", "Russian game", shop-salon Neo, Alexander Klyachin and ZKI, representative offices of LG, Pioneer for help in the preparation of material.