Choosing acoustics for a car is far from a simple task, since it requires at least fundamental knowledge of the theory of car audio. In addition, in any case, you need experience in installing and configuring equipment, because after careless installation, the owner of the acoustics may encounter background noise, low-quality sound and other problems.
Buying expensive acoustics is not a panacea for future sound problems. Full functioning of speaker systems is only possible if they have been professionally installed. Thus, we can conclude that the correct configuration and installation of the speaker is more important than its cost. In this article we will answer which acoustics to choose and what to look for when purchasing acoustic components.
Types of columns
When thinking about which audio system to choose for your car, you first need to understand the types of speakers. All speakers for audio systems are usually divided into two categories - coaxial and component.
What is coaxial acoustics
Coaxial speakers are a speaker that is a structure of several speakers that reproduce different frequencies. Depending on the crossover built into the design of this type of speakers, they are usually divided into two-way, three-way, 4..5..6..etc. To find out how many bars there are in coaxial speakers, you just need to count the speakers. We would like to draw your attention to the fact that to reproduce all audio frequencies Three stripes are enough.
Acoustics that have 4 or more bands sound very squeaky and are not particularly pleasant to listen to. The advantages of coaxial acoustics include ease of installation and low cost.
Why do we need component acoustics?
Component acoustics are speakers of different frequency ranges, which are located separately. These professional speakers are distinguished by high sound quality. This is due to the fact that speakers with different frequencies are not located in the same place.
Thus, you can get full pleasure from listening to music, since the sound is disassembled into individual components. However, for any pleasure you have to pay: such speakers are an order of magnitude more expensive than coaxial ones, and installing component acoustics requires much more effort.
Comparison of component and coaxial acoustics
The quality of sound reproduction, price and ease of installation are not all that distinguish coaxial acoustics from component ones. Another fundamental difference between these two types of speakers is the location of the sound in the car interior. The disadvantages of coaxial speakers include the fact that they make the sound highly directional. The speakers in the front doors are component acoustics. High frequencies, if they are directed at the feet, are very difficult to hear; thanks to the separated components, the tweeters are installed higher, for example, on a car panel and directed towards the listener. Thus, the detail of the sound increases manifold, the music begins to play not from below but from the front, the so-called stage effect appears.
Diffuser and suspension material
Any professional description of loudspeakers must contain information about the material from which they were made. The following materials can be used for the manufacture of diffusers: paper, polypropylene, bextren, titanium, magnesium, aluminum and so on.
The most common are paper diffusers. During their production, sheets of paper are compressed, after which they are given a conical shape. But it is worth saying that, in fact, almost all paper diffusers can be classified as a composite type, since other synthetic materials are used in their production process. Famous manufacturers never disclose what materials are used, because each of them has its own proprietary recipe.
- The advantages of paper diffusers include detailed sound, which is created due to high-quality internal damping. The main disadvantage of paper diffusers is considered to be their low strength, as a result of which the sound power in the audio system is limited.
- Diffusers made of polypropylene have a more complex design. They have a neutral sound and excellent impulsive characteristics. At the same time, such diffusers are more resistant to mechanical and atmospheric influences than paper diffusers.
- Diffusers made of titanium and aluminum began to be made in Germany in the 80s. Their production is based on vacuum deposition technology. Domes made from these materials have the best sound quality: the sound is transparent and clear.
In conclusion regarding this section, I would like to say that manufacturers have learned to do good acoustics from almost any material, there are even speakers made of precious metals, but they are very expensive big money. We advise you to pay attention to speakers with a paper cone; they have a very decent sound and have been tested by more than one generation.
It is also necessary to pay attention to what material the outer suspension of the diffuser is made of. The suspension can be made of the same material as the diffuser, and also protrude separate element in the shape of a ring made of rubber, polyurethane or other material. One of the highest quality and most common suspensions is rubber. It must maintain linearity over the range of motion of the loudspeaker system, and also have flexibility as this affects the resonance frequency.
A subwoofer is the same speaker that is capable of reproducing only low frequencies "".
Acoustic power and sensitivity
Many people are interested in how to choose speakers for a car radio, but they do not understand what is meant by such a parameter as power. There is a misconception that the higher the power, the louder the speaker will play. However, in practice it turns out that a speaker with a power of 100 W will play quieter than a speaker with half the power. Thus, we can conclude that power is not an indicator of sound volume, but of the mechanical reliability of the system.
The volume of the speakers to some extent depends on their power, however, it is not directly related to this parameter. It makes sense to pay attention to the power of an audio system only in cases when it comes to purchasing acoustics for an amplifier. However, in this case, only the rated power (RMS) is important, since other numbers will not provide any useful information the buyer and will only mislead him. But even RMS sometimes has little to do with reality, so it is fair to say that the power indicator is extremely uninformative for potential speakers buyers.
The size of speaker magnets is also deceptive because high-end audio systems use neodymium magnets. Despite the fact that they are quite unremarkable in appearance, their magnetic properties are slightly higher than those of ferrite magnets. In practice, this means that the sound of the former is much stronger. Due to their miniature size, neodymium magnetic systems also have a shallow seating depth, which simplifies their installation in a car.
Sensitivity is a parameter of audio systems that shows the intensity sound pressure. The higher the sensitivity, the louder the sound, but only if the specified power is supplied to the speakers. For example, a speaker with low power paired with a powerful amplifier can produce louder sound than a speaker with high level sensitivity. The unit for measuring sensitivity is decibel divided by the threshold of hearing (dB/W*m). Sensitivity is affected by parameters such as sound pressure, distance from the source, and signal strength. However, it is worth noting that you do not always need to rely on this parameter because some speaker manufacturers measure sensitivity under non-standard conditions. Ideally, sensitivity should be measured at a distance of no more than one meter when a signal of one watt is applied.
When choosing a speaker for your car, ask the seller what sensitivity this speaker has? Low sensitivity is 87-88 db; we recommend choosing acoustics that have a sensitivity of 90-93 db.
Brand
Another recommendation that can be given to those who are thinking about choosing a specific manufacturer is not to chase a low price and be careful when purchasing speakers from unknown manufacturers. No matter how tempting the sellers’ words may be, you should not pay attention to these tempting offers, since it is always better to turn to manufacturers that have long proven themselves in the market.
They have decades of experience in speaker manufacturing, value their reputation, and therefore produce only high-quality products.
The answer to the question of how to choose acoustics for a car is no longer as simple today as, for example, ten years ago, because there are a large number of manufacturers on the market (more than 200). The dominance of Chinese speaker systems significantly complicated the task. You should not completely neglect Chinese products, because with a tight budget, buying a speaker system from China will not be so bad decision. But the problem is that there are a large number of unscrupulous sellers on the market who present audio systems made in China as a branded product from American or European manufacturers. In this case, the buyer who decided to spend a couple of hundred rubles will buy “branded” acoustics for $100, when its real price does not exceed $30.
If we consider this criterion as a specific sound, then for a more natural sound it is recommended to buy European audio systems (Morel, Magnat, Focal, Hertz, LightningAudio, JBL, DLS, BostonAcoustic, this is not the whole list). We also recommend that you refrain from purchasing such companies as (Mystery, supra, Fusion, Sound max, calcel). These manufacturers have a very ridiculous price, but the sound quality of these speakers is appropriate. Speaker systems from Sony, Pioneer, Panasonic, JVS, Kenwood are also very good options, but some of their owners complain about average sound quality. If you are looking for the ideal combination of parameters such as price and quality, then it is best to contact the manufacturers listed above.
How to choose speakers good video from the Ural company
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A portable speaker allows you to listen to music anywhere: in the park, while hiking on Kok-Zhailau or while doing sports. There are hundreds of such devices on the market, and the greater the choice, the greater the chance of making a mistake. Often the choice is made based on appearance or time battery life, but we believe that these are not the main criteria. Choosing a speaker is no easier than choosing a speaker system. There's a lot to consider technical characteristics.
No. 1. What kind of speaker is called portable?
"Portable" does not mean "small". It is believed that portable speaker It should definitely fit easily into a backpack or even a pocket. But it also happens that the speaker has decent dimensions and weighs five or even ten kilograms. Therefore, portability is primarily not about size or weight, but about ease of connection and sound adjustment, as well as the ability to work autonomously without connecting to the network.
No. 2. What types of portable speakers are there?
In a good way, the speaker can replace a home audio system. Moreover, it has several advantages over its bulky counterparts: the wires do not dangle, the speaker can be placed anywhere, and sound control is available from anywhere within the range of the network. And a stylish speaker will decorate your interior. And most importantly, you can take it with you on vacation at any time to continue enjoying the music. For example, the Sony SRS-XB30 model is made of polycarbonate with a rubberized coating and moisture protection according to the IPX5 standard.
No. 3. Fine. Is the sound reproduction technology the same in all speakers?
No. From a technology point of view, speakers are divided into three types:
- Mono column. There is only one speaker, sometimes quite loud, but don't expect surround sound.
- Stereo speaker. Two or more speakers sound much more interesting than one, but only with sufficient volume and the correct location relative to the listener.
- Systems 2.1. There is also a subwoofer, so you should listen to high-quality rock on these models, although they are not very compact.
No. 4. Who needs a portable speaker?
Not everyone can afford a sophisticated speaker system, but the sound of a computer or smartphone is often not enough. A compromise solution is a portable speaker.
The ancestors of modern portable speaker systems were portable tape recorders with built-in speakers (remember those huge things?). At least thirty years have passed since then, but the purpose of the equipment remains the same: portable acoustics allow the owner and his entourage to listen to music where they want, and as loud as their heart desires.
As for sound, modern speakers have also gone far ahead. They are capable of reproducing bass and adequately displaying the acoustic-frequency picture with all the dynamic nuances. Of course, they still have to grow to achieve full-fledged sound, but at the current stage, portable speakers are showing tremendous progress.
No. 5. How to choose a column?
The effectiveness of any gadget depends on the conditions in which it will be used. It’s illogical to buy a three-kilogram suitcase for cycling with the breeze and music, and with a tiny pocket device there’s no point in throwing parties on the beach. It is best to choose the golden mean - a column that will open to its maximum under different conditions. As with full-format speaker systems, volume, clarity and detail are important here.
Speakers weighing a kilogram are often considered a compromise. In addition, some models, in particular the Sony SRS-XB30, have a mode Party Chain, with which you can connect up to 10 speakers in one bundle and increase the sound power tenfold. In addition, Sony has NFC technology - fast wireless connection with a small coverage area between all brand devices. This is actually Party Hard mode.
No. 6. But does battery size matter?
Certainly. You will still be carrying a portable speaker with you, so its operating time should be enough for 4-6 hours. These are average figures for the market, but during long trips, of course, more time is needed for battery life. In the case of the Sony SRS-XB30, it all depends on whether the backlight works, for example, and in what climatic conditions the device is located (ideally, we are talking about 24 hours of uninterrupted operation). Sony speaker Thanks to the large battery capacity, the SRS-XB30 can be effectively used not only for its intended purpose, but also as a power bank for your mobile phone.
No. 7. What else should you pay attention to?
Number of speakers and their size. Sometimes this is visible through the grid, sometimes the parameters are honestly indicated by the manufacturer. A speaker with one driver will not sound as clear at full volume as a speaker with separate drivers. A speaker with one channel sounds in mono mode, a speaker with two channels sounds in stereo. The difference between mono and stereo sound is spatial sound: mono sound does not have volume.
Dimensions. All for the same reason as above, this must be taken into account: too voluminous or heavy acoustics will not be very convenient when traveling. On the other hand, you can proceed from your needs: decide for yourself what is more important to you - power or compactness.
Control. Even if a portable speaker is synchronized via Bluetooth, it is desirable that you can control music and volume from the case. Often the speaker is controlled via Bluetooth - in Sony models The SRS-XB30 has a Hands Free function that allows you to answer calls handsfree without interrupting the connection with the speaker and without spoiling the atmosphere at the party.
Power. output power does not affect the sound quality, but indicates the maximum sound volume of the speaker. The starting point is 1.5 W per speaker. Such a speaker will sound a little louder than a smartphone. A speaker with average performance has a power of 16-20 W, and 60 W is already a monster, similar in sound to basic multimedia acoustics. By the way, pay attention to the presence of a subwoofer in the column - its power is taken into account separately.
No. 8. How do you know if you like the sound of a speaker?
First of all, pay attention to your personal feelings. Just like with headphones, nothing matters if the sound is not pleasing to your ears. But if you still want to figure it out, then you should again pay attention to the number of speakers - they provide the frequency range. The wider the frequency range, the better the sound. Portable acoustics reproduce high frequencies within the range of 10,000-55,000 Hz. “Bass” - within the range of 20-500 Hz: the lower this indicator, the richer the sound. Speakers come with all sorts of additional features, depending on the manufacturer. In the case of Sony, this is a function Extra Bass, which enhances the sound low frequencies.
No. 9. Where and why is the column needed?
The volume of a smartphone will be low in open spaces, and stationary systems need an outlet. A portable speaker is a compromise option: its power is comparable to inexpensive home acoustics. It can be connected to a laptop or tablet to watch movies with high-quality, loud sound. It will not take up much space in a suitcase or travel bag. You can connect your smartphone via Bluetooth without getting up from your lounge chair.
In some models, manufacturers expand the functionality to customize the product to the user's needs. If you are a party lover, then you probably know that not only music is important for a quality atmosphere, but also the right light. So, Sony has implemented a multi-color linear backlight and a strobe on the front side of the speaker, which are most conveniently controlled via Sony app Music Center.
It's hard to imagine now Personal Computer without speakers. Many are even surprised if the computer is without them. In this case, watching movies, listening to music and playing games is simply not possible. Therefore, when purchasing a computer, everyone tries to immediately buy all the necessary components, incl. columns.
It is worth noting that speakers don't produce high quality sound. Therefore, for those who value high-quality sound while watching a movie or listening to music, it is recommended to immediately purchase stereo systems for a home theater. Computer speakers are more suitable for people for whom sound quality is not a priority. But even in this case, choosing good speakers is not an easy task. They must be small in size, suppress magnetic radiation, have special connectors and be compatible with the computer's sound card.
Types of computer speakers
There are active and passive speakers. Active speakers have a built-in amplifier. Passive speakers are used for laptops and require an amplifier and additional power. Passive speakers have poor sound and low cost. That's why they lose active speakers that provide high-quality sound.
Columns are distinguished by configuration. In this case they can be 2.0, 2.1, 4.1, 5.1 and 7.1. The simplest speakers of modification 2.0. They have two speakers and no additional devices or amplifiers. Speakers from other modifications have more parts, as well as a subwoofer.
Columns 2.0 and 2.1 have average price and are designed for listening to music, videos and games. They are quite sufficient for home or office use. May have one or more speakers. The 2.1 modification speakers have a subwoofer, which is responsible for outputting low frequencies, while the speakers are responsible for outputting high and medium frequencies. In this case, the sound becomes more voluminous and realistic.
5.1 and 7.1 speakers allow you to fully immerse yourself in the gameplay or watching a movie. They have multiple channels and the sound quality is much better than the two previous configurations. But here it is very important that the speakers fit the sound card the computer itself. 5.1 and 7.1 modification speakers allow you to create a home theater.
The 5.1 modification has two front, two rear, one center speaker and a subwoofer. Modification 7.1 resembles 5.1, but only supplemented with two more rear speakers.
What to look for when choosing speakers?
When choosing speakers, you should always pay attention to the material of manufacture. The sound quality largely depends on the material. Plastic speakers reduce sound quality and are cheap. From such speakers you can only expect rattling, poor sound reproduction and many other troubles. Wooden speakers, on the contrary, allow you to create high-quality sound and good acoustic properties. But here you may encounter the high cost of speakers. Solid wood speakers are produced only for professional use. For other cases, wood is replaced with chipboard, MDF and multi-layer plywood. Speakers made of any material should not have any holes, because they degrade the sound. The exception is the bass reflex, which has holes on the front side for bass playback.
But still the material is not main characteristic high quality sound. It is necessary to pay attention to speakers, amplifiers, filters, build quality and speaker system settings.
Before we begin to consider the technical characteristics that you need to pay attention to when choosing speakers, it is worth noting that many consider power and volume to be the same indicator. This is a misleading opinion. Power affects acoustics, and volume is related to sensitivity. Sound volume parameters should not be higher than 85 decibels.
Now let's talk more about the technical characteristics.
Power
There are two types of power - peak music power (P.M.R.O - Peak Music Power Output) and root mean square power (RMS - Root Mean Square). When choosing, you should pay attention to the second type of power. It characterizes the maximum power at which the speaker system can reproduce sounds for a long time without distortion or damage. With this power, comfortable and high-quality music reproduction occurs. Peak musical power can be several times higher than the second power.
For a computer that does not have special requirements and will be placed in an average-sized room, it is enough to have a power of 20-50 watts.
Speaker range frequency
This parameter refers to the frequency that the speakers are capable of reproducing. The ideal playback frequency is 20-20000 Hz, but they are only found in professional acoustic systems. In ordinary columns, the characteristics often indicate a frequency from 40 Hz to 18 kHz. In principle, this is enough for a person to normally perceive high-quality sound. If the frequency is lower or higher than the specified parameter, the sound will be accompanied by crackling, hissing, dip and distortion. In addition, it is worth considering that a cheap speaker system cannot have a frequency of 20-20,000 Hz. This is not true.
Sensitivity
This parameter, which directly affects the sound volume and indicates the level of sound reproduction at a distance of one meter at a power of 1 W. The indicator is measured in decibels. The optimal option is considered to be a sensitivity of 85-89 decibels.
If you purchase speakers that have different sensitivity, then best sound will come from a speaker with greater sensitivity.
Number of lanes
This parameter characterizes the number of speakers. Single-way speaker systems have one speaker. A two-way speaker consists of two speakers, where one speaker reproduces low-frequency sounds, and the second one reproduces mid- and high-frequency sounds. Three-way speakers have three speakers. The first speaker produces low sounds, the second - mid-range sounds, and the third - high-pitched sounds.
There are speaker systems with more than three bands. In this case, the sounds are more colorful.
Size
For many, this parameter may not play a role during selection. But, if, after all, the speakers should not attract attention, then you should choose a size so that you can hide them. The best option is speakers measuring 10.4x16.5x15 cm. They can be hidden behind the computer.
Control
The control panel (basically the volume control) is located either on the subwoofer or on one of the speakers. On the column it can be on the side, front or back. It is best to control the speakers from a computer. Frequent use of the volume control leads to its erasure and failure.
Modern speakers are wired or remote controls management
How to choose speakers?
When buying speakers, it's worth doing a little test. Turn on the speakers and gradually increase the volume. Stop at the moment when the sound begins to distort. Listen to the sound and determine if it is enough for you to listen to music, watch a movie or play games.
Additional functions
An excellent addition to the speakers would be the presence of a headphone output, a control panel, an information display, a function for playing radio or music from a memory card or flash drive.
Speaker Manufacturers
Speakers are produced by a fairly large number of companies. Therefore, we will focus on the most popular companies that are in demand among buyers.
Creative, Defender, Edifier, F&D, Logitech, Microlab and Sven companies produce high-quality speaker systems. The speakers are not cheap, but the sound quality is worth the money.
Cheaper options for speakers that are in demand among users are presented by A4Tech, Acme, Codegen, Gembird, Gemix, Genius. But, unfortunately, the sound is quite bad.
Acoustic systems for laptops are produced by A4Tech, Defender, Divoom, HQ-Tech, Jabra, Philips, Sanyoo, Sony, Speed-Link.
Price
The cost of the speakers depends on the modification. The cheapest speakers are modifications 2.0 and 2.1. They cost from $10 to $50. The 5.1 and 7.1 modification acoustic system costs over $70.
Where to buy speakers?
You can purchase speakers at an electronics store or online stores. But before you make a purchase, you should decide on the parameters that the speakers should have and the brand, and also not rush into the purchase.
How to use speakers?
Using the speakers is quite simple. First they need to be connected to the computer. After that, turn on the sound and adjust the volume. Next, choose your favorite music or movie and enjoy.
First of all, let's understand the terms, since the concepts of “loudspeaker”, “column”, “speaker”, “speaker system” are often used at random, creating a fair amount of confusion.
Speaker is a device designed to effectively radiate sound into the surrounding space in an air environment, containing one or more loudspeaker heads with acoustic design and electrical devices (filters, regulators, etc.).
In the domestic technical literature, an erroneous practice has developed, according to which the term “loudspeaker” (LS) is used mainly for a single loudspeaker (in foreign catalogs it is defined as loudspeaker units or loudspeaker drive element, or driver). In accordance with the requirements of GOST 16122-87, a single loudspeaker must be designated as speaker head .
The term is often applied to a set of Hi-Fi and Hi-End class loudspeakers acoustic system (AC) (acoustical system or loudspeaker system). The sound system includes acoustic speakers .
Depending on their purpose, speakers vary significantly in parameters, design and construction. The main types of acoustic systems presented on the modern market can be divided into several categories depending on their area of application:
- Speakers for home use, which in turn can be divided into systems:
- mass;
- Hi-Fi categories and High-End;
- Speakers for home audio video complexes of the “Home-Theater” type;
- for modern computer systems(AC Multi-Media), etc.;
- Speakers for sound and sound reinforcement systems, including conference systems and speech translation systems (these include, in particular, ceiling speaker systems);
- concert and theater speakers;
- studio speakers;
- automobile (and transport) speakers;
- Speakers for individual listening (stereo headphones).
Speaker device
AC may be single lane And multi-lane . Single-band speakers are used, as a rule, in mass-produced equipment in the budget sector. High-quality speakers (Fig. 1) use a multi-way design principle, since the use of one broadband loudspeaker head does not allow for high quality sound.
The AC usually consists of:
- speaker heads, each of which (or several simultaneously) work in their own frequency range;
- housing;
- filtering and correcting circuits, as well as other electronic devices (for example, for overload protection, level indication, etc.);
- audio cables and input terminals;
- amplifiers for active speaker systems and crossovers (active filters).
Rice. 1. Defender sound system
Speaker heads
Loudspeaker heads are classified by operating principle, by emission method, by transmitted frequency band, by area of application, etc.
According to the operating principle , i.e. Based on the method of converting electrical energy into acoustic energy, loudspeakers are divided into electrodynamic, electrostatic, piezoceramic (piezo-film), plasma, etc.
The vast majority of loudspeaker heads are electrodynamic ("dynamic" or simply "speakers"). Their operating principle is based on the movement in a constant magnetic field of a conductor or coil powered by alternating current (Fig. 2).
Rice. 2. Electrodynamic coil loudspeaker
The head of the electrodynamic loudspeaker consists of a moving system, a magnetic circuit and a diffuser holder (1).
The moving system includes a suspension (2), a diaphragm (3), a centering washer (4), a dust cap (5), a voice coil (6) and flexible leads.
When alternating current is passed through a voice coil placed in the radial gap of a magnetic circuit, a mechanical force will act on it. Under the influence of this force, axial vibrations of the coil and the diaphragm attached to it occur. The design of an electrodynamic loudspeaker is very similar to the design of a dynamic microphone, so, in principle, you can make a weak loudspeaker head from a dynamic microphone, and a microphone from a loudspeaker head. It is clear that all this will work disgustingly, but it will work.
Rice. 3. Ribbon speaker
Ribbon speakers (Fig. 3) use a thin metal strip that is placed in a magnetic field between the poles of a magnet and serves as both a current conductor and an oscillating radiating element.
Tape heads are much more effective than dynamic, piezoelectric and others, because if the area of a conical or dome diffuser is the area of a visible circle, then the active area of a tape emitter is the full development of the folded membrane (the effective area is 2.5 times larger than the projection area of the folded tape). Thus, less movement of the diffuser is required to achieve the required sound pressure level.
Rice. 4. Electrostatic loudspeaker
Electrostatic loudspeakers (Fig. 4) use a radiating element in the form of a thin metallized film (1) with a thickness of about 6...10 microns, placed between perforated electrodes (2) (i.e., it is a variable capacitor, where one of the plates is a thin metallized movable membrane). A high polarizing voltage of the order of 8...10 kV is applied between the membrane and the electrodes. An alternating sound voltage, under the influence of which the membrane vibrates and emits sound, is supplied to fixed electrodes. Loudspeakers of this type provide purity and transparency of sound due to low levels of transient distortion.
Rice. 5. Final range of electrostatic loudspeakers
Rice. 6. Electrostatic speaker center speaker. Model 200
In Fig. 5 shows the Final range of electrostatic loudspeakers, and Fig. 6 – close-up of the central speaker.
Rice. 7. Piezo film loudspeaker
Piezoceramic (piezo film) loudspeakers (Fig. 7) are used mainly as a high-frequency link in acoustic systems. As an exciting element, they use a bimorph element obtained by connecting two plates (1), (3) made of piezoceramics (titanium zirconate, barium titanate, etc.). The bimorph element is fixed on both sides; when an electrical signal is supplied, bending deformations occur in it, which are transmitted to the diaphragm connected to it (2). A variation of this type of loudspeaker is piezo-film emitters; they use high-polymer films, which, using specially developed technology, are given piezoelectric properties (when polarized in a strong magnetic field). If such a film is shaped into a dome or cylinder, then under the influence of an alternating voltage applied to it, it begins to vibrate and emit sound; such loudspeakers do not require the use of a magnetic circuit.
According to the method of emitting acoustic energy, loudspeaker heads are divided into direct radiation heads, in which the diaphragm emits sound directly into environment, and horn (Fig. 8), in which the diaphragm emits sound through the horn. If the horn loudspeaker has a pre-horn chamber, then it is called a narrow-throated horn loudspeaker, and if only a horn is used, then it is a wide-throated horn loudspeaker.
Rice. 8. Horn loudspeaker
Horn loudspeakers are widely used in creating sound systems for streets, stadiums, squares, sound reinforcement systems in various rooms, high-quality household systems, warning systems, etc.
The reasons for the spread of horn loudspeakers are due, first of all, to the fact that they are more efficient, their efficiency is 10-20% or more (in conventional loudspeakers the efficiency is less than 1...2%); In addition, the use of rigid horns allows the formation of a given directivity characteristic, which is very important when designing sound reinforcement systems. However, when using horn loudspeakers, problems arise due to the fact that in order to emit low frequencies it is necessary to significantly increase the size of the horn, and high sound pressure levels in the pre-horn chamber create additional nonlinear distortions.
The design of loudspeaker heads depends on the frequency band in which they must operate. Based on this feature, loudspeakers are divided into:
- broadband (OO “full-range”);
- low-frequency (reproducible range approximately 20-40...500-1000 Hz) (“woofer”, “subwoofer”);
- mid-frequency (range 0.3-0.5...5-8 kHz) (“mid-range”);
- high-frequency (1-2..16-30 kHz) (“tweeter”), etc.
Most of the power of audio signals usually comes from low frequency GG, so they must withstand loads of up to 200 W or more, while maintaining thermal and mechanical strength. These GGs have a low resonant frequency (16...30 Hz) and must be designed for a large stroke of the moving system up to ±12...15 mm.
The appearance of a modern low-frequency GG for high-quality speakers is shown in Fig. 9.
The main radiating element of a loudspeaker is the diaphragm. The diaphragms of modern low-frequency GGs are made from complex compositions based on natural long-fiber cellulose with various additives. Sometimes such a composition includes up to 10-15 components. Synthetic film compositions based on polyolefins (polypropylene and polyethylene) and composite materials based on Kevlar fabric are increasingly used.
Rice. 9. Woofer
Speakers for home theaters (especially the center and front channels, as well as the subwoofer) require the use of carefully shielded low-frequency generators.
Midrange speakers (MF GG) are used in the frequency range from 200... 800 Hz to 5...8 kHz, where the sensitivity of hearing to all types of distortion is maximum, therefore the requirements for their quality are the most stringent.
Tweeters (HF GG). (Fig. 10). Requirements for them have increased sharply in recent years due to an increase in the spectral power density in the high-frequency part of the spectrum in modern electronic music, an expansion of the frequency and dynamic range of programs reproduced by digital sound reproduction equipment, etc.
In modern speakers, high-frequency GGs are used, as a rule, in the frequency range from 2...5 to 30...40 kHz. It is extremely difficult to ensure equivalent high-quality sound reproduction in such a wide range using one GG. Therefore, most of the currently produced HF GGs are used in the range from 2... 5 to 16... 18 kHz, and in some speakers additional small-sized HF GGs are installed (reproducing frequencies from 8... 10 to 30... 40 kHz).
Rice. 10. HF GG
Ceiling speakers
Ceiling speakers are typically electrodynamic cone speakers housed in plastic or metal housings. They are used for sounding rooms and in emergency warning systems for buildings. Thanks to the large angle of the sound radiation pattern and the wide range of reproduced frequencies, ceiling speakers are capable of reproducing sound quite well, in addition, they fit harmoniously into almost any interior.
Ceiling speakers provide a more uniform sound distribution throughout the room compared to other speakers and do not require the installation of powerful amplifiers. Their use is especially effective for sounding large rooms with a ceiling height of up to 5 m.
For ease of installation, the ceiling loudspeaker housing is equipped with special devices: spring-loaded stops, runners or brackets. Many speakers are attached to ceiling tiles with screws. Unlike “conventional” PA systems, ceiling speaker systems are high voltage, with a typical line voltage of 100V, so ceiling speakers have built-in transformers.
When designing a public address system, the calculation of the required number of ceiling loudspeakers and their placement diagram (Fig. 11) is made based on the required sound pressure level at listener ear level (usually an average value of 1.5 m is taken). For rooms with a ceiling height of less than 5 meters, such a calculation is not difficult and is made using approximate formulas. Table 1, for a given ceiling height and room area, shows the number of ceiling speakers that will give best quality sound and the most uniform distribution of sound waves.
Rice. 11. Layout of ceiling speakers
The S parameter in the table is the approximate area covered by one ceiling loudspeaker:
S = (2x(H – 1.5 m))2, where H is the ceiling height.
Table 1. Calculation of the warning system
| P | 103,5 | 101 | 99 | 97,5 | 96 |
| P/2 | 100,5 | 98 | 96 | 94,5 | 93 |
| H/S | 3 | 3,5 | 4 | 4,5 | 5 |
| 25 | 2 | 1 | 1 | 1 | 1 |
| 35 | 3 | 2 | 1 | 1 | 1 |
| 50 | 4 | 2 | 1 | 1 | 1 |
| 80 | 6 | 3 | 2 | 2 | 1 |
| 100 | 7 | 4 | 3 | 2 | 2 |
| 150 | 10 | 6 | 4 | 3 | 2 |
| 200 | 13 | 8 | 5 | 4 | 3 |
| 300 | 20 | 11 | 7 | 5 | 4 |
| 400 | 26 | 15 | 10 | 7 | 5 |
| 500 | 33 | 19 | 12 | 8 | 6 |
| 600 | 40 | 22 | 14 | 10 | 8 |
| 700 | 46 | 26 | 17 | 12 | 9 |
| 800 | 53 | 30 | 19 | 13 | 10 |
| 900 | 59 | 33 | 22 | 15 | 11 |
| 1000 | 66 | 37 | 24 | 17 | 12 |
In the table:
P – sound pressure at 1.5 m when the ceiling loudspeaker is operating at full power;
P/2 – sound pressure at 1.5 m when the ceiling loudspeaker operates at half maximum power;
H – ceiling height;
S – area of the room.
If the ceiling height is more than 5 meters, installing ceiling speakers is not recommended. However, if you must use in-ceiling speakers, you should take steps to improve the uniformity of sound distribution and reduce the effect of reverberation (echo). If ceiling speakers are placed too close together, the sound will be distributed unevenly at listeners' ear level. If you increase the distance between adjacent speakers, the sound pressure level may not be sufficient for good audibility. Increasing the sound level of the speakers in this case entails an increase in reverberation, especially in rooms decorated with glass, marble, etc. Reverberation can be reduced using sound-absorbing materials: carpets, tapestries, curtains, etc.
In Fig. Figures 12 and 13 show examples of in-wall and mounted ceiling speakers from Kramer Electronics.
Speaker housing. Main types of buildings and their purpose
The speaker housing performs a variety of functions. In the low-frequency region, it blocks the “acoustic short circuit” effect that occurs due to the addition of emitted sound from the front and rear surfaces of the diaphragm in antiphase, which leads to the suppression of low-frequency radiation.
The use of a housing makes it possible to increase the intensity of radiation at low frequencies, as well as to increase the mechanical damping of loudspeakers, which makes it possible to “smooth out” resonances and reduce the unevenness of the amplitude-frequency response. The body has a significant impact not only in the low range, but also in the mid and high frequencies. A properly designed and manufactured enclosure has a huge impact on sound quality.
When designing speaker enclosures, design options such as an endless screen, a closed enclosure, an enclosure with a bass reflex, a labyrinth, a transmission line, etc. are most often used.
Infinite screen occurs when speakers are installed in the wall of a room with a sufficiently large volume behind it. This type of speaker installation is characterized by a “booming” effect at low frequencies, since there is no damping.
Closed housing. Modern speakers mainly use closed compression-type enclosures. The principle of operation of compression design is that they use loudspeakers with a very flexible suspension and a large mass, i.e. low resonant frequency. In this case, the elasticity of the air in the body becomes the determining factor; it is it that begins to make the main contribution to the restoring force applied to the diaphragm.
Housing with bass reflex– a housing in which a hole is made, which allows the use of radiation from the rear surface of the diffuser. The maximum effect is achieved in the region of the resonance frequency of the oscillatory system, formed by the mass of air in the hole or pipe and the mass of air in the housing.
Cases with a bass reflex (Fig. 14 a) have many varieties. A housing using a special pipe inserted into the hole allows you to reduce the dimensions of the housing and adjust the bass reflex by adjusting the dimensions of the pipe (Fig. 14 b).
If a passive (i.e. without a magnetic circuit) loudspeaker is installed in the housing opening, the oscillations of which are excited by fluctuations in the volume of air enclosed in the housing, then such a housing is called a housing with a passive radiator (Fig. 14 c).
Rice. 14. Speaker housing with various bass reflex options: a – bass reflex; b – bass reflex with pipe; c – passive radiator
Labyrinth is a variant of the case with a bass reflex, in which special partitions are installed. When the length of the labyrinth reaches 1/4 of the wavelength at the resonant frequency of the woofer, it acts similarly to a bass reflex. The use of a labyrinth expands the possibilities for tuning to lower frequencies. Harmonic resonances from the main resonant frequency of the pipe are damped by sound-absorbing materials on the walls of the housing (Fig. 15 a).
Rice. 15. Speaker housing of labyrinth type (a) and transmission line type (b)
Transmission line- This is a type of labyrinth. It differs from a labyrinth in that the entire volume of the body is filled with sound-absorbing material, and the cross-section of the line is made variable - larger at the cone, smaller at the hole (Fig. 15 b). This type of enclosure is very difficult to configure.
If two identical GGs are installed in the case on one bass reflex, then this is called “low-frequency design with a symmetrical load.” This design is often used in subwoofers.
Speakers with smoothed corners, a streamlined shape, and an asymmetrical oscillator arrangement sound better, but producing the enclosures of such speakers is difficult and expensive, so the vast majority of speakers are produced in rectangular-shaped enclosures. To reduce diffraction effects at the corners of the front panel, special measures are used, including the placement of sound-absorbing materials (“acoustic blanket”), optimization of the ratio of the dimensions of the front panel and the depth of the cabinet, selection of asymmetrical arrangement of loudspeakers, etc.
The desire to shift diffraction peaks and dips in the frequency response to a higher frequency region and thereby reduce their influence forces the use of the narrowest front panels. The complex external configurations of many modern speakers are driven not only by aesthetic considerations, but also by the desire to reduce diffraction effects. To reduce sound radiation from the walls of speakers, they usually try to increase their rigidity and mass.
In modern speakers, the housing is a rather complex and expensive structure (Fig. 16). As a criterion for the effectiveness of measures taken to soundproof a housing, it is generally accepted that the difference between the sound pressure level emitted by the walls of the housing and the sound pressure level from the acoustic system as a whole should be at least 20 dB.
Rice. 16. Section AC
In addition to objective measurements, during design, speakers are listened to in enclosures of various designs.
Filtering and correction circuits
It is almost impossible or difficult to ensure high-quality sound reproduction using single-way speakers, so they are used only in budget decisions, for example, in cheap computer speakers. High-quality speakers, with rare exceptions, are multi-way. In order to supply each GG with signals of its own frequency subrange, electrical isolation filters (“crossovers”) are used.
Most speakers for home use use the so-called. passive filters that are connected between the amplifier and loudspeaker (Fig. 17).
Rice. 17. Passive filters (“passive crossovers”) in speakers
Passive filters are usually placed inside speakers, increasing their weight and dimensions. Passive filters in speakers are of first, second, third and fourth order. The slope of the first order filters is 6 dB/octave, the second is 12 dB/octave, the third is 18 dB/octave and the fourth is 24 dB/octave.
The simplest filters are first-order filters; they take up little space and are inexpensive, but have insufficient passband rolloff steepness. A positive feature of these filters is the absence of phase shift between the tweeter (HF head) and the other speaker.
Second-order filters (or Butterworth filters, named after the creator of the mathematical model of these filters) have higher sensitivity, but give a phase shift of 180 degrees, which means that the membranes of the HF head and the other speaker are not synchronized. To fix this problem, you need to change the polarity of the wires on the Twitter.
Third-order filters have good phase characteristics for any connection polarity. In Fig. 18 shows the frequency response of a third-order filter, and Fig. 19 – its electrical diagram.
Rice. 18. Frequency response of a third-order filter
Rice. 19. Electrical diagram third order filter
Rice. 20. Frequency response of a three-band filter
In three-band speakers, the frequency response of the filter looks as shown in Fig. 20.
Fourth-order Butterworth filters have a high passband rolloff steepness, which dramatically reduces the interference of speakers in the frequency separation region. The phase shift is 360 degrees, that is, in practice it is absent. However, the problem is that the phase shift of such filters is not constant, which can cause unstable operation of the speakers. Linkwitz and Riley succeeded in optimizing the fourth-order filter circuit in relation to speakers. Their filter consists of two series-connected second-order Butterworth filters for the HF GG and for the LF GG. This filter has no phase shifts and allows for time correction for speakers that do not emit sound in the same plane. These filters provide the best acoustic performance.
“Active” speakers with built-in multi-band amplifiers use active filters connected before the amplifier and also called crossovers (Fig. 21).
Rice. 21. Using crossovers
Compared to passive filters, active filters have a number of advantages: smaller dimensions, better tunability of crossover frequencies, greater stability of characteristics, etc. However, passive filters provide more dynamic range, lower level of noise and nonlinear distortion. Their disadvantages include temperature instability, which leads to a change in the shape of the frequency response when the level of the input signal increases (the so-called “power compression”), as well as the need for careful selection of high-precision elements (resistors, capacitors, etc.), to the spread of parameters which filter characteristics can be very sensitive. In recent years, a number of foreign companies have begun to use digital filters in acoustic systems, providing real-time filtering, correction and adaptation functions to real listening conditions.
In addition to filters, modern acoustic systems often use electronic devices to protect loudspeakers from thermal and mechanical overloads. Protection from both long-term and short-term (peak) overloads is carried out using various versions of threshold circuits, the response thresholds of which must be less than the thermal constants of the loudspeaker heads (T = 10...20 ms). In addition, many household systems use various overload indication options.
Main characteristics of the speakers
There are quite a lot of characteristics of speakers, some of them are of greater importance for the user, others are less important, domestic and foreign characteristics of speakers and methods for measuring them do not always coincide. We will briefly consider only the main characteristics of the speaker.
Efficient worker (effectively reproduced) frequency range - a range within which the sound pressure level developed by the speaker is not lower than a given one, in relation to the level averaged in a certain frequency band. In the recommendations of IEC 581–7 minimum requirements to this parameter are 50 – 12500 Hz with a drop of 8 dB relative to the level averaged in the frequency band 100 – 8000 Hz.
The value of this characteristic greatly influences the natural sound of the acoustics. The closer the operating range of the speaker is to the maximum range perceived by the human hearing organs (16 – 20,000 Hz), the better and more natural the speaker sounds. The effective operating range depends on the characteristics of the loudspeaker heads, the acoustic design of the speakers and the parameters of the crossover filter.
At low frequencies, the volume of the speaker cabinet plays a decisive role. The larger it is, the more efficiently low frequencies are reproduced, which is why subwoofers in particular are always quite bulky. There are usually no problems with reproducing high frequencies, since modern tweeters can even reproduce ultrasound. Often the range of reproduced frequencies of speakers exceeds the upper limit of human audibility. It is believed that in this case the timbre of a complex phonogram, for example, symphonic music, is more accurately conveyed. Typical values: 100 – 18000 Hz for bookshelf acoustics and 60 – 20000 Hz for floor-standing.
Serious speaker manufacturers usually provide a graph of the sound pressure developed by the speaker depending on frequency (amplitude-frequency response (AFC) graph), from which you can determine the effective operating frequency range of the speaker and the unevenness of the frequency response.
The degree of unevenness of the frequency response is characterized by the ratio of the maximum value of sound pressure to the minimum, or according to another method, the ratio of the maximum (minimum) value to the average, in a given frequency range, expressed in decibels. The recommendations of IEC 581-7, which define the minimum requirements for Hi-Fi equipment, indicate that the frequency response unevenness should not exceed ±4 dB in the range of 100 - 8000 Hz.
Directional characteristic allows you to evaluate the spatial distribution of sound vibrations emitted by an acoustic system, and optimally position the acoustic systems in different rooms. This parameter can be judged by the loudspeaker's radiation pattern, which is the dependence of the sound pressure level on the angle of rotation of the loudspeaker relative to its operating axis in polar coordinates, measured at one or several fixed frequencies. Sometimes the decline in the amplitude-frequency response when the speaker is rotated at a certain fixed angle is displayed on the main graph in the form of additional branches of the frequency response.
Characteristic sensitivity is the ratio of the average sound pressure developed by the speaker in a given frequency range (usually 100 - 8000 Hz) on the operating axis, reduced to a distance of 1 m and an input electrical power of 1 W. In most Hi-Fi speaker models, the level of characteristic sensitivity is 86-90 dB (in technical literature, dB/m/W is often indicated instead of dB). There are high-quality wideband speakers with a sensitivity of 93 - 95 dB/m/W and more.
Characteristic sensitivity determines what dynamic range the speaker can provide. The wide dynamic range allows you to reproduce complex musical works with great reliability, especially jazz, symphonic, and chamber music.
Harmonic distortion factor characterizes the appearance during the conversion process of spectral components that were absent in the original signal, distorting its structure, that is, ultimately, the accuracy of reproduction. This is a very important parameter, since the contribution of speakers to the total nonlinear distortion coefficient of the entire audio path, as a rule, is maximum. For example, the THD factor modern amplifier is hundredths of a percent, while the typical value of this parameter for AC is a few percent. As the signal power increases, the nonlinear distortion factor increases.
Electrical (acoustic) power – determines the sound pressure level and dynamic range (taking into account the characteristic sensitivity) that the speakers can potentially provide in a certain room.
Several types of power, defined by different standards, are used:
Characteristic power , at which the speaker provides a given level of average sound pressure. The IEC recommendations set this level to 94 dB at a distance of 1 meter.
Maximum (maximum) noise or rated power at which the speaker can operate for a long time without mechanical and thermal damage when tested with a special noise signal, close in spectrum to the real one music programs(pink noise). According to the measurement methodology, it coincides with the nameplate power defined in domestic standards.
Maximum (limit) sinusoidal power – the power of a continuous sinusoidal signal in a given frequency range, at which the speaker can operate for a long time without mechanical and thermal damage.
Maximum (ultimate) long-term the power that the acoustics can withstand without mechanical and thermal damage for one minute, with the same test signal as for the rated power. The tests are repeated 10 times with an interval of 1 minute.
Maximum (limit) short-term the power that the speaker can withstand when tested with a noise signal with the same distribution as for the nameplate power for 1 second. The tests are repeated 60 times with an interval of 1 minute.
Peak (maximum) musical power – a favorite parameter for characterizing speakers of unknown origin. The measurement technique, defined by the German standard DIN 45500, is as follows: a signal with a frequency below 250 Hz and a duration of less than 2 seconds is supplied to the speaker. The acoustics are considered to have passed the test if there are no audible distortions. It is clear that “distortions noticeable to the ear” can be understood as anything. As a result, no one can use the speaker enclosures famous manufacturers stickers like “P.M.P.O.” appear. … (or Musical Power…)…100!, …200! and even... ...1000 Wt! It is clear that there is no need to talk about any quality sound created by such speakers.
When choosing speakers for ULF, it is desirable that the real maximum power The speaker exceeded the power of the amplifier by approximately 30 percent or more. In this case, you will be insured against failure of the acoustics due to the supply of a signal to it at an unacceptably high level. Of course, good speakers have overload protection circuits, but it’s better not to take risks.
What amplifier power is sufficient for high-quality sound reproduction? This is largely determined by the parameters of the room, the characteristics of the acoustic systems, and the needs of the listener himself. When choosing an amplifier for sounding a small living room, we can assume that the power of the amplifier should be at least 20 W.
Most common values electrical (input) resistance (impedance): 4, 8 or 16 ohms. This parameter is important when choosing an amplifier with which the speakers will work. You should use speakers with a resistance corresponding to that specified in the amplifier's data sheet. Such a solution will ensure ideal matching of the characteristics of the acoustics and amplifier, that is, the best sound quality.
Measuring the characteristics of speakers in conditions different from the conditions of specially equipped acoustic laboratories of manufacturing plants is an extremely complex, expensive matter and, most importantly, gives very approximate results. High-quality sound analyzers and measuring microphones with preamplifiers that meet all international measurement requirements are extremely expensive and not every Russian company can afford to purchase them. True, modern measurement techniques in most cases will make it possible to do without an acoustically attenuated chamber.
Audio cables
Audio cables are, at first glance, the least important component of the audio subsystem of an installation or home theater, so they are often purchased as a spare item. And they make a serious mistake.
It is clear that any cable affects the signal passing through it. The question is how exactly the cable affects the signal and how strong this effect is.
The choice of audio cables is determined by the quality of the audio signal on the one hand and structural and financial considerations on the other. Indeed, some installations require laying hundreds of meters of audio cables. You can calculate how much, for example, silver microphone cables with a total weight of 100 kg will cost...
The conductors in any electrical cable or wire are metals. Audio cables primarily use copper and silver. In 1984, Hitachi released the SAX-102 interconnect cable, which immediately attracted the attention of professionals. It was made from so-called oxygen-free copper OFC (Oxygen Free Copper). Now such copper is used by almost all specialized “cable” companies. What is good about oxygen-free copper? A conductor metal can be thought of as a series connection of metal granules. Inside each granule, the crystal structure remains ideal, but the interfaces between granules disrupt the crystal lattice. As a rule, the causes of the appearance of interfaces are films of oxides and oxygen compounds with metals. By molding and stretching the OFC in a specific manner, the length of the ideal granules increases. Regular high purity copper contains about 5,000 granules per meter of cable. Improvements in OFC technology have led to the emergence of higher quality oxygen-free high-conductivity copper OFHC (Oxygen Free High Conductivity), the number of granules per meter in which was 1000. There are other types of technology for producing oxygen-free copper wires.
Similar technologies are applied to silver conductors. The result is the appearance of long-grained silver with high degree cleaning, for example, FPS (Functionally Superior Silver) from AudioQuest or PSS (Perfect Surface Silver). These are very expensive wires. Silver is often used as a cladding coating on copper wire, and to eliminate the potential influence of inhomogeneities on signal transmission, the surface is polished to a mirror finish.
As insulators for audio wires and cables in household appliances The materials used are mainly polyethylene, polyvinyl chloride and fluoroplastic (known as Teflon). For external coatings of cables, artificial rubbers, silicone rubbers, polypropylenes, etc. are used. Polyethylene is most often used; fluoroplastic has the best dielectric characteristics, but it is relatively expensive, which limits its use. Sometimes foamed polyethylene or fluoroplastic is used as an insulator.
Since audio cables connect the amplifier to the speakers and operate with fairly large currents, developers first of all pay attention to the active resistance of the conductor: the lower it is, the better. Firstly, because the ohmic resistance of the cable is connected in series with the output resistance of the ULF and the input resistance of the speaker, and a relatively high-resistance connecting wire can sharply deteriorate the quality of operation of the ULF and speaker, and, secondly, according to the Joule-Lenz law, the thermal heating of the wire is proportional to the second degree of current flowing through it. Reducing the ohmic resistance of conducting lines is achieved by increasing their cross-section. Therefore, audio cables are quite thick. Acoustic wires are relatively low-frequency (the operating range is within 4-5 orders of magnitude: from a few hertz to hundreds of kilohertz). And yet, most developers, having achieved a minimum value of resistivity (0.001–0.05 Ohm/m), try to reduce the inductance of the wire (the typical value of specific inductance is 0.2–0.5 μH/m). Almost all wires, with the exception of flat ribbon wires, are made in the form of bundles assembled from individual thin wires. The simplest ones are a pair of insulated conductors (“noodles”); This design is most common due to its lowest cost. The twisted veins constantly change their position: some go inward from the surface, others, on the contrary, go from the center to the surface. Since the distribution of current density across the cross-section of the conductor does not change to remain near the surface of the cable, the current passes through the interface from one conductor to another. It happens that the contact between individual cores is not always good (on the surface of each core there is a layer of oxides that conduct current poorly), and numerous transitions through resistance barriers can theoretically affect the transmitted signal. If you cut an old network cable in rubber insulation, a dark film of oxides attracts attention. Such a wire cannot be soldered without stripping; the ohmmeter shows a fairly high resistance...
To reduce the influence of the skin effect, each thin core is sometimes equipped with its own insulation, however, such cables are low-tech, since it is difficult to automate the process of cutting the cores of such a cable.
Speaker cables are characterized by a wide variety of designs, differing not only in their internal structure, but also in their external features: round in cross-section, flat, like thin ribbons, single, double, quad, etc. Despite their high cost, flat wires are very popular in home theater installations because they are easily hidden under wallpaper, carpets, etc. Double wires in pairs are in demand, which are convenient for connecting acoustics using Bi-Wiring and Bi-Amping schemes.
A variety of speakers are home theater speakers, which have specific requirements. They will be discussed in a separate brochure.
It's always nice to listen to music or watch good film with high quality sound. Today, the choice of audio systems is simply huge, and it is easy for a person who is poorly versed in such technology to get confused. Find out how to choose speakers for home use based on your preferences. The speaker system should not only have an attractive appearance, but also optimal parameters for specific purposes. Any speaker system consists of a configuration that can be designated by the numbers 2.0, 2.1, 3.1,5.1, 7.1. The first number in this marking indicates the number of speakers (satellites), and the second indicates the presence of a subwoofer. That is, if the speakers are designated as 2.0, this means that they do not have a separate low-frequency speaker (subwoofer), and the lower bass is built into the speakers themselves. Dividing the system into main speakers and a subwoofer allows you to get higher quality, surround sound, creating the effect of presence. The more accompanying speakers the system has, the better and more impressive the sound. Let's look at what types of columns exist: These are the main types of home speakers that can be purchased today on our market. Large and beautiful-looking speakers may have very weak characteristics. Conversely, compact and unprepossessing ones are capable of surpassing larger systems in power and clarity of sound. Exactly from technical parameters Sound quality depends. To choose truly good speakers, you need to learn to understand the basic performance criteria. It is worth immediately noting that the power indicator is not an indicator of volume. This factor indicates how long the speaker can sound at maximum volume without distortion, wheezing or other interference. It is important that the power level of the speakers be lower than the power level of the amplifier. Otherwise, the system will very quickly burn out from excessive load. The parameters distinguish between two types of power - peak and root mean square. Regardless of what type of speakers you choose, you should pay attention to the RMS indicator. It determines how long a speaker can play at high volumes without distortion or overload. The optimal indicator for home acoustics can be considered the total power of the speakers in the range of 40-70 W. This characteristic indicates the number of speakers in the column. For example, small computer speakers most often have only one band. 3.1 systems can consist of 2-way speakers. Three-way audio systems are considered one of the best, where the division is into high, mid and low frequencies. There are also more advanced systems that divide the sound into 4-5 and even 7 channels. The more bands an acoustic system has, the better and more versatile its sound. Amplitude-frequency response (AFC) is the dependence of the amplitude of sound vibrations at the output on the frequency of the reproduced signal. The frequency response is usually depicted on graphs. The range of these frequencies is displayed in hertz and kilohertz, and any deviations in decibels. In the equipment passport it is indicated in hertz (Hz) and kilohertz (kHz). This important indicator, but for a person who does not understand all the intricacies of musical equipment, it is useless. If we talk in simple words, then the smoother the frequency response graph when the speaker sounds, the better. Sudden fluctuations and bursts indicate that the speakers are distorting the sound. To choose the right audio system based on frequency response parameters, it is better to consult with a specialist. Today, there are various digital audio encodings that allow you to reproduce it in volume. First the “stereo” effect appeared, then formats such as Dolby Stereo Surround. These encodings involve dividing the sound into several channels, thereby achieving the effect of presence and complete immersion in the sound. Not every speaker system is capable of reading and reproducing sound in multi-channel encodings. Single-way speakers can also provide stereo sound, but they will not be able to convey all the luxury of a multi-channel system. Those who want to listen to audio files in modern surround encodings on their speakers should buy 3.5 or 7-channel speakers and a player that reads formats such as Blu-ray. High-quality modern speaker systems are equipped with a bass reflex. This is a kind of pipe or hole located in the speaker housing. The resonance of this element allows you to expand the low-frequency range. In systems consisting of small satellites and a subwoofer, the bass reflex is installed only in the low-frequency speaker. For small rooms, it is better to choose speakers with a side or front bass reflex placement. In large halls, speakers with side and rear placement of this part are used. Speakers are made from a variety of materials. The quality of the cabinet also affects the sound. Types of materials from which audio system housings are made: The most popular today are plastic speakers. Good durable plastic does not distort the sound and is quite suitable for lining speakers. In addition, it is the cheapest material. The best equipment is considered to be wooden. Natural wood has unique acoustic properties and improves sound. Stone is suitable for large and low-frequency speakers; it muffles bass distortion. Systems made of MDF and chipboard would be a good choice. But glass and metal do not have the best effect on the reproducibility of sound notes. A lot depends on the number of bands, the size of the speakers and the room. TO additional functions This includes wireless control (using a remote control), as well as the ability to configure each speaker separately. Such options are present in more expensive models. Some systems are equipped with a display that shows all the current settings. A very convenient extension that allows you to configure the speakers not only auditorily, but also visually. Some speakers may have an additional wall mount. This is very convenient for those who have a small computer desk (if the system is purchased specifically for a PC). If we compare wireless speakers and ordinary ones, then in terms of sound quality the latter clearly win. Despite the convenience of portable audio systems, the wireless signal loses some of the power and purity of the sound. So, now you know how to choose speakers wisely, taking into account their parameters and characteristics. We present a rating of the best home models with optimal parameters and good reviews. A small stereo pair of speakers (2.0) has an output power of 24 W and a front bass reflex. The acoustics are designed for tabletop placement. The speakers are perfect for a computer. The body is made of MDF in a stylish black color. The equipment looks expensive and solid. The model has a frequency range of 70-20000 Hz and digital amplifier class D. The speakers are designed according to a 2-way design, based on 4-inch bass speakers. On the back of the case there are toggle switches for adjusting the reproduced volume and bass level.Main characteristics and their importance
Speaker power
Number of lanes
Amplitude-frequency characteristics
Audio coding system
Bass reflex
Housing material
Additional functionality
Rating
- the switch is at the back, it’s not always convenient to reach for it;
- few high frequencies;
- Not very high quality wires.
The Edifier R12U model is a practical choice of speakers for a tablet or computer. Small but powerful speakers squeeze out a total of 4 watts. On the front panel of the acoustics there is a bass reflex and a toggle switch. The body is made of plastic and comes in 3 colors: red, black, white.
The range of reproduced frequencies of the speakers is 180-20000 Hz. The speakers are connected via a USB connector. The model also has a mini jack linear output and a headphone jack.
- light, compact;
- there are controls on the front of the case;
- very good bass;
- absolutely silent when inactive;
- cheap.
- at maximum volume they may wheeze a little (depending on the music);
- glossy plastic gets dirty quickly;
- If you use it for a long time and at loud volumes, they get very hot.
The 2.1 speaker system in an elegant design has a total output power of 38 W. Distinctive feature The model is able to be mounted on a tabletop or on a wall. The body is made of MDF, which has a positive effect on sound quality. The range of reproduced frequencies is 20-20000 Hz. On the front of the case there are controls through which you can adjust the treble and bass. The bass reflex on the subwoofer significantly enhances the bass.
The sound quality of this acoustics will please both computer game lovers and music lovers.
- clear, high-quality sound on all ranges;
- high level of strength, last a very long time;
- very high quality casing that does not wear out over time;
- very powerful volume, glass may rattle in a small room;
- possibility of adjusting bass and treble;
- no noise from mobile phone.
- short wires.
The SOLO-2 model is positioned as an audio system for a player or computer. Its power is enough to fill a large room in the house with sound. The equipment body is made of MDF with a dark wood look. The bass reflex is brought to back panel. The total power of the speakers is 60 W, which is an excellent indicator. On the rear panel there are volume, treble and bass controls. Used in audio technology powerful amplifier with a chip from ST Microelectronics. This keeps distortion at high volumes to a minimum.
If we compare models in the rating, the first place should be given to the SVEN SPS-820 acoustics. She has the best price-quality ratio. It will allow you to arrange a real disco at home, enjoy immersion in computer game, watch a good movie comfortably.
But we should not forget that everything depends on the personal preferences of each user. And if speakers are needed only for light musical accompaniment while working on a PC, then there is no need to buy expensive ones. Whereas for music lovers, it makes sense to fork out for a more “sophisticated” audio system.
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