Speakers: specifications, types

The general specialization of the acoustic system.

Nowadays, this indicator distinguishes home, concert, monitor, information, outdoor and cinema systems, as well as solutions for expanding existing speakers. At the same time, the appointment is not a categorical prescription — many models also allow non-standard use cases. However, it is easier and more convenient to choose a column in accordance with the method of application that was originally intended for it. The specific features of acoustics for various purposes are as follows:

— Home. A kind of speaker designed, as the name implies, for individual use at home. Note that the characteristics of such models can be different — from the simplest bookshelf speakers to powerful multi-band speakers designed for home theaters and high-quality audio systems.

— Concert. A distinctive external feature of speakers designed for concerts is their large dimensions and high rated power (in some models it exceeds 1 kW). The latter is indispensable for vast spaces — halls, stadiums, etc. — where the sound must also “shout out” the reaction of the listeners (sometimes quite loud). But it makes no sense to purchase such speakers for home use — not only because of the high cost, but also because instead of hig...h-level inputs (as in home speakers), such systems have a connector for special equipment, musical instruments, etc. Most often, concert acoustics are sold in 1.0 configurations (see "Number of channels") in the expectation that sound engineers can assemble the desired acoustic configuration from a certain number of components.

— Monitor room. The main purpose of monitor acoustics is sound quality control; accordingly, all such models are distinguished by extremely high accuracy of transmission of all sound details, smooth frequency response and almost complete absence of distortion. This makes them indispensable for professional use (for example, in recording studios): a monitor speaker will allow you to very accurately determine all the shortcomings of the incoming signal, including amplifier noise, audio editing inaccuracies, etc. Like concert systems (see above), such systems are usually equipped with specialized inputs, but it makes no sense to use monitors for home listening for another reason: all sound flaws that are imperceptible on ordinary acoustics will then appear — and can significantly spoil the impression . And the price of such models is very high.

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— Outdoor. Acoustic systems designed for outdoor installation. They can be used, for example, for sound accompaniment of holidays in the country or in nature, playing music in the summer areas of cafes, etc. All models of this type necessarily have a waterproof and corrosion-resistant housing (see "Moisture protection") in case of adverse weather conditions; in addition, they are usually additionally protected from ultraviolet radiation. Outdoor acoustics can be mounted in different ways (see above), however, hanging options are most common.

— Cinema. Models designed, in accordance with the name, for use in cinemas — and not so much in the halls of the "home" format, for 6-10 spectators, but in large-format entertainment complexes for tens and hundreds of seats. Cinema speakers have the following common features. Firstly, they are all made passive, counting on connection to specialized amplifiers; accordingly, high-voltage connectors in the form of terminals or Euroblock sockets are used as inputs. Secondly, the power of such devices is quite high — from 100 W and above. Thirdly, cinema acoustics are usually produced in 1.0 format (see "Number of channels") — in other words, such models are not ready-made acoustic systems, but only separate components from which a specific multi-channel speaker is assembled. This output format makes it possible to accurately select the speakers needed for a particular hall. By type of installation, cinema acoustics usually refers to floor, built-in or wall-mounted. The latter variety is most often designed for installation on the side walls, and the first two are behind the screen. At the same time, floor versions can actually consist of two parts — a classic speaker for low frequencies and a horn for midrange and treble.

— Expansion of the acoustic system. A specific type of acoustics, which initially does not involve independent use and is used as an addition to traditional speakers. Such models are used mainly in multi-channel surround sound systems — to expand the sound stage vertically; they have a characteristic appearance: relatively small dimensions, an inclined top panel and a speaker built into this panel. Thus, the sound from the speakers is directed at an upward angle — in order to be reflected from the ceiling, reach the listener and give the impression that the sound source is from above. The use of "expanding" acoustics allows you to do without the use of specialized ceiling speakers. This is especially convenient in light of the fact that in-ceiling speakers are usually made built-in and rather difficult to install, while expansion modules often allow installation directly on the main speaker components. Also note that this type of acoustics can be initially designed for certain models of the main speakers; this point should be clarified before buying.

Possibility of using an acoustic system for monitoring the near field. Monitoring is called sound quality control - for example, during recording in a studio; for this, columns of the corresponding purpose are used (see above). The term "near field" means that acoustics are designed for use at a short distance - up to 1.5 m from the listener; such speakers have a relatively low power and are best suited for small rooms (as well as other conditions where there is no extensive space or it is not required) - in particular, amateur and even home studios.

— Outdoor. As the name implies, these speakers are designed for installation on the floor and have a corresponding design: for example, in most models, the cabinet has a large height, selected in such a way that the speakers are at the optimum height when placed on the floor. In addition, floor acoustics are designed with the calculation of the influence of the floor itself on the sound; this allows you to achieve evenness and good depth of low frequencies. Floorstanding speakers in general have the highest power among all types and are usually designed for large rooms.

— Shelf. Shelf speakers are relatively small in size and are designed to be placed on shelves or stands of a different kind, at a significant elevation from the floor (the optimal height is considered to approximately correspond to the location of the listener's head). The advantage of this placement is smooth sound at all frequencies. In addition, such models usually have less power than floor standing ones and are well suited for small spaces — besides, the shelves can be mounted on the wall like a wall speaker.

— Floor / shelf. This type includes multi-channel (see "Intended use") systems in which one part of the speakers is designed for floor installation, the other for shelf installation. The former usually include front an...d, sometimes, rear speakers, as well as a subwoofer, while the latter include a centre channel and low-power rear speakers. See above for floor and shelf installation details.

— Embedded. Speakers designed to mount directly into the ceiling or wall. Often such models do not have a case at all — its role is played by niches in which speakers are installed. According to the shape of the case, namely the mounting hole, such acoustics can be round, oval, rectangular and square. The main advantage of embedded systems is that they take up a minimum of space in the room, moreover, they can be made almost invisible, and in general they are easier to fit into the design than any other type. At the same time, built-in speakers are the most difficult to install, require the participation of a qualified specialist, and it is also very difficult to rearrange an unsuccessfully installed speaker.

— Wall. Such speakers are very similar to bookshelf speakers in a number of characteristics (see above): in particular, they are small in size and power and are designed to be installed at the level of the listener's ears. The key difference is its own mounting system, thanks to which wall-mounted models do not require shelves or other supports and are hung directly on the wall during installation. This led to another difference — acoustic characteristics: they are designed for the fact that there will be a blank wall behind the speaker. Because of this, wall models should not be placed on shelves, even if the design allows it — the sound will be far from optimal. In addition to options with a traditional design, wall acoustics also include the so-called "dipole" speakers: These have 2 speakers facing in different directions and are designed to be mounted on the side wall in premium home theater systems for maximum surround sound.

— Suspended. As the name suggests, speakers of this type are suspended from the ceiling or other base on flexible mounts during installation — these can be either cables or their own cables. Most ceiling models are informational (see "Purpose"); this is due to the fact that one of the easiest ways to block a large room is to install an omnidirectional speaker under the ceiling. At the same time, high-end home systems can also be suspended: the fact is that such placement maximally removes the speaker from shelves, walls, etc., and thus minimizes distortion caused by foreign objects (especially since they are not are always made from acoustically optimal materials).

— Landscape. In addition to an unusual appearance for acoustic systems and stylization for elements of landscape design, this type of acoustics also boasts very stable cases. So, speakers, usually, are not afraid of temperature changes, direct sunlight or precipitation. At the same time, they are designed to play music in open space. They can be freely installed in the yard, many manufacturers initially complete their solutions with a special mounting system to protect the acoustic systems from theft.

— Linear array. A line array is an acoustic system in which several speakers are stacked vertically, directly one above the other. Due to this, such a system generates cylindrical sound waves (rather than spherical, as in classical acoustics). Such waves are distinguished by good “range”, the volume of linear arrays does not decrease as the distance increases as much as that of conventional speakers. This allows you to achieve a uniform and loud sound even in large spaces such as stadiums or concert halls. But at short distances (of the order of several metres), such characteristics are not required. Therefore, the main field of application of line arrays is concert acoustics (see "Purpose").

General cabinet shape for built-in speakers (see "Installation").

This feature is practically not related to the performance of the speakers — it only determines the shape of the outlet, which is required for the selected acoustics, and has primarily aesthetic meaning. It doesn’t make much sense to describe in detail the different options, we just note that nowadays you can find columns with a double designation on the market — “round / rectangular”. It means that this model is equipped with two sets of frames of different shapes, and the buyer can choose a specific shape at his discretion. However, such universality is rarely required in fact, and therefore this variant has not received distribution.

— Active. Acoustic systems equipped with their own built-in power amplifier. A line-level signal (from the preamp) is sufficient for these speakers, making them extremely easy to use. On the other hand, the built-in amplifier requires power, so these speakers have to be plugged into an outlet as well.

— Passive. Speaker systems that do not have a built-in power amplifier. Accordingly, you need to connect such speakers to an external amplifier (or a device that has such an amplifier — for example, an audio receiver), while paying special attention to component compatibility. On the other hand, passive acoustics are considered more suitable for creating high-end audio systems than active ones: it allows you to choose a power amplifier of your choice, moreover, there are no “extra” electronics in the speaker cabinet, which reduces the likelihood of interference.

— Passive / active. Acoustic systems combining passive main speakers with an active subwoofer. For a number of technical reasons, active subwoofers are more convenient than passive ones: in particular, they save the user from having to look for a specialized low-frequency amplifier, and they provide more tuning options (the latter can be useful for “fitting” sound into a particular room). Therefore, many manufacturers produce passive-active kits.

— 1.0. Single-channel(monophonic) audio system. "Alone" such speakers do not provide a sense of surround sound, but can be used as separate components for multi-channel surround sound systems.

— 2.0. Normal stereo sound: two speakers responsible for the left and right channels. Allows you to create a minimal illusion of "surround" sound by simulating the displacement of the sound source in the space in front of the listener.

— 2.1. A dual speaker system that creates a minimal illusion of "surround" sound, and a subwoofer that delivers powerful and rich sound by adding bass and ultra-low frequencies.

— 3.0. System of three speakers(centre and two front). According to some manufacturers, such systems in small rooms are capable, with some tricks, of reproducing full surround sound without rear speakers.

— 5.0. A set of five speakers(two front, centre and two rear), which allows you to reproduce a full surround sound, which is subjectively perceived by the listener not only in front, but also behind him.

— 5.1. A set of five speakers and a subwoofer for low and ultra-low frequencies, allowing you to reproduce a full surround sound, which is subjectively perceived by the listener not only in front, but also behind him. 5.1 systems ar...e one of the most popular multi-channel audio formats, widely used, in particular, in home theaters.

There are also much rarer options due to narrow needs:

— 1.1. Systems in the form of a subwoofer, on which a general range speaker is installed on top. They are found mainly in concert acoustics — it is convenient to assemble systems for powerful and rich sound from such components.

— 2.2. Further development of the idea embodied in systems 1.1 (see above); in fact, these are sets of two identical columns of 1.1 format. Such sets are produced from the considerations that for concerts, especially in relatively small rooms, it is often enough just a pair of 1.1 speakers; it is more convenient and often cheaper to buy two such speakers at once than to buy them one at a time.

— 3.1. A system of three speakers (centre and two front), as well as a subwoofer for bass and ultra-low frequencies. It is a "stripped down" version of the 5.1 system; according to some manufacturers, such systems are capable of reproducing full surround sound in the absence of rear speakers, due to which they are perfect for installation in small rooms where it is not possible to place full-fledged 5.1 acoustics.

— 4.0. A variation of 4.1 systems (see below), devoid of a subwoofer, otherwise completely similar.

— 4.1. Simplified version of 5.1 format (see above); such systems usually lack either a centre or one of the rear channels. Anyway, other things being equal, they are cheaper than full-length 5.1, but their sound quality is significantly lower.

— 4.2. This category includes mainly concert acoustics (see "Intended use"), which is an extended version of the 2.2 described above. In 4.2 systems, not one, but two total range speakers are installed above each subwoofer. Thus, you can achieve better and richer sound.

— 5.2. A variation of the 5.1 described above, supplemented by a second subwoofer — this has a positive effect on the quality and accuracy of bass reproduction. On the other hand, setting up such systems is somewhat more complicated.

— 6.1. Extended version of 5.1 format: two front speakers, a centre speaker, three rear speakers (left, right and centre) and a subwoofer for bass and extra bass. It is characterized by a more accurate transmission of surround sound in the rear sector, but is quite rare.

— 7.0. Extended version of multi-channel audio with five main channels (eg 5.1). In this case, the five main channels are supplemented with two more, which allows to achieve a more voluminous and reliable sound. Most often, additional channels are located at the back ("rear right" and "rear left"), but depending on the specific sound format, other installation options are possible — for example, on the sides of the user.

— 8.1. Systems providing 8 main sound channels plus 1 low frequency. The specific distribution of the main channels may be different, depending on the model. However, all 8.1 systems differ, on the one hand, in good reliability of surround sound, on the other hand, in high cost and complexity in setting up.

The number of individual speakers provided in each speaker. Do not confuse this parameter with the number of bands described below — several speakers can be responsible for one band; it is believed that this can improve some of the sound parameters, in addition, it allows you to achieve high power with relatively small speaker dimensions. Otherwise, the number of speakers is more of a reference than a practically significant indicator.

If there are speakers with a different number of speakers in the set, the maximum value of this parameter is usually indicated (most often — by the front speaker). In this case, passive radiators(if any, see "Design Features") are not taken into account in the calculation.

The number of distinct frequency bands into which the sound is divided when played back through the speakers. For each such band, a separate speaker is provided, and sometimes several (for more details, see "Number of speakers").

Among multi-band consumer-level models, the most common options are 2 or 3 bands — LF / HF and LF / MF / HF, respectively. A larger number, usually, indicates a high class of acoustics, because. it is more accurately capable of reproducing the signal and, accordingly, is more complicated. But there are also small satellites with one speaker ( single-way) for the case of an undemanding listener.

Note that, in addition to integers, models are also produced with a fractional number of bands — for example, 2.5 or 3.5. This marking indicates the presence in the design of a speaker that is responsible for two bands at once: for example, model 2.5 has separate speakers for bass and treble plus a combined bass + midrange (similar in design to bass, but also loaded with mid frequencies).

Speaker sensitivity.

This characteristic is indicated on the basis of how loud the acoustics are capable of producing when a signal of a certain standard power is applied to it. Simply put, the higher the sensitivity of the speaker, the louder it will sound at the same output power of the amplifier. Thus, sensitive acoustics can be effectively used even in combination with relatively low-power "amplifiers". On the other hand, low sensitivity also has its advantages: it allows you to achieve a more uniform frequency response and reduces the likelihood of overloading the amplifier. In the least sensitive modern speakers, this indicator does not exceed 84 dB, in the most sensitive it is 95 – 96 dB or more.

Note that in fact, you have to pay attention to this parameter when acoustics are planned to be used with a separately selected power amplifier. Therefore, for active systems (see "Type"), sensitivity is purely a reference value, and, usually, it can be ignored when choosing.

Impedance is the nominal electrical impedance of a speaker system. Nowadays, a set of standard impedance values are used; the most widely used speakers are 4 ohms, 6 ohms, 8 ohms and 16 ohms.

This parameter is of primary importance for passive acoustics (see "Type"). When connecting such speakers to a power amplifier, it is highly desirable that their impedance matches the speaker impedance for which the amplifier is designed; in case of a mismatch, either overload and distortion in sound (if the speaker impedance is below optimal), or a decrease in power (in the opposite case), are possible.

As for active acoustics, here the impedance is mainly of reference value — the speakers in such systems are initially selected for the corresponding amplifiers. However there is an opinion that a higher resistance reduces the level of interference and has a positive effect on the purity of the sound; however, the difference in impedance between different models is usually not so great that this effect is noticeable against the background of other factors that determine sound quality.

The frequency of the crossover provided in the speaker design.

The crossover is installed exclusively in the model with several stripes (see "Number of stripes"). This is an electronic filter that separates the incoming audio signal into separate frequency bands and directs each band to its "own" set of speakers. And the crossover frequency shows where the border between these ranges passes. If there are more than two bands, then there will be several similar boundaries: for example, for a four-band system, “0.15 / 0.8 / 2.8 kHz” or “0.12 / 1 / 3.8” may be indicated.

In most cases, this parameter is mainly of reference value: the built-in crossover frequencies are selected according to the performance of the speakers installed in the speaker.

Rated power of one front speaker. See "Total Power Rating" below for details on power rating. Here we note that the higher the power, the louder the system component can sound — of course, with a properly selected amplifier. In addition, this parameter is very important for matching with the amplifier: it is desirable that the output power on the corresponding amplifier channel be less than the power of the speaker. If the incoming signal is more powerful, distortions in the sound and even damage to the speakers are possible, and if it is weaker, then the sound volume will decrease (in other words, it will not be possible to use the full potential of the acoustics), but this moment will be critical only for listening at maximum volume.

Rated output of the rear speaker. See "Front" above for details on power rating.

Rated power of the centre speaker. See "Front" above for details on power rating.

The highest power rating of an amplifier that the loudspeakers can handle safely. Too much input power can damage the speakers, so when connecting, make sure that the amplifier's characteristics do not exceed the capabilities of the speakers. It is worth noting that this parameter may be slightly higher than the total nominal power of the acoustics (see below), since in this case we are only talking about the safety of the equipment, and not about the absence of distortion in the sound.

The total rated power of all speaker components, in other words, the sum of the powers of all speakers. As a nominal one, they usually indicate the highest average (rms) power at which acoustics can operate for a long time without overloads and damage. In this case, individual power surges can significantly exceed this value, however, it is the rated power that is the main characteristic of any speaker.

First of all, the sound volume depends on this characteristic: the more powerful the speakers, the louder the sound they can produce if there is a suitable amplifier. In addition, in passive and passive-active models, compatibility with an external amplifier also depends on the power: the output power of the “amplifier” should not exceed the power of the acoustics connected to it, otherwise overloads and even breakdowns are possible.

Detailed recommendations regarding the choice of speakers for power for a particular situation can be found in special sources. However, in general, an indicator of up to 100 W by the standards of modern acoustics is considered quite modest, 100 – 200 W — average, 200 – 300 W — above average, and the most powerful sets give out up to 500 W or even more.

In conclusion, we note two more nuances. Firstly, when comparing different systems according to this ch...aracteristic, one must also take into account the sound format in which they work. In particular, if there is a subwoofer, it can account for a significant part of the total power — up to half or more. As a result, for example, a 2.1 set of 50 W with a 20-watt subwoofer at the main frequencies will not be able to pull out the same volume as a 40-watt 2.0 system: in the first case, each main channel will have only 15 watts, in the second — 20 watts. Secondly, in multichannel systems, the total power can be distributed among the channels in different proportions; so, say, two 5.1 systems with the same total power can differ markedly in front and rear balance at maximum volume.

The range of audio frequencies that the front speaker can reproduce. See "Total Frequency Range" below for details on this setting.

The range of audio frequencies that the rear speaker is capable of reproducing. See "Total Frequency Range" below for details on this setting.

The range of audio frequencies that the centre speaker is capable of reproducing. See "Total Frequency Range" below for details on this setting.

The total frequency range that the speaker is capable of reproducing. Specified from the bottom of the range in the lowest frequency component to the top of the range in the highest frequency: for example, in a 2.1 system with main speakers at 100 – 22000 Hz and a subwoofer at 20 – 150 Hz, the total value will be 20 – 22000 Hz.

The wider the frequency range — the fuller the reproduced sound, the lower the likelihood that some part of the low or high frequencies will be "cut off". It is worth noting here that the human ear perceives frequencies on average from 16 Hz to 22 kHz, and from a practical point of view, it makes no sense to provide a wider frequency range in speakers. However, quite a few models go beyond this range, sometimes quite significantly (for example, there are speakers with a range of about 10 – 50,000 Hz). Such characteristics are a kind of "side effect" of high-end acoustics, and they are usually given for advertising purposes.

Thus, the lower limit of the range in modern speakers can be within frequencies up to 20 Hz, however, higher values \u200b\u200bare more common — 30 – 40 Hz, 40 – 50 Hz, or even more than 70 Hz. In turn, the upper limit in most modern speakers lies in the range 19 – 22 kHz, although there are deviations both upwards (see above) and downwards.

The type of subwoofer included with the speaker.

— Closed. The simplest type of subwoofer: a woofer placed, as the name suggests, in a closed cabinet. Such models provide good sound quality, it is not as susceptible to distortion as the bass-reflex models described below — on the other hand, they are less sensitive.

— Phase inverter. Subwoofers equipped with so-called phase inverters — tubes brought out of the case to the outside. The length of the phase inverter is such that the signal coming out of it is inverted in phase relative to the signal from the speaker (hence the name). It is believed that this has a positive effect on the sound power; at the same time, the movement of air in the tube creates some noise and may affect the clarity of the sound.

— With a passive emitter. The passive radiator looks like an ordinary speaker — however, it is devoid of a coil and a magnet and is not a sound source, but only repeats the vibrations from full-fledged speakers. The purpose of this function is similar to the phase inverter described above, while the advantageous difference between passive radiators and phase inverter tubes is the absence of noise from the air flow.

The rated power of the subwoofer provided in the speakers.

The more powerful the subwoofer — the louder and richer bass the acoustics can produce. In addition, this characteristic determines compatibility with an external amplifier (if its connection is provided by the speaker design): the output power of such an amplifier on the bass channel should not exceed this indicator. And best of all, when the power ratings of the amplifier and subwoofer are the same — this allows you to fully realize all the capabilities of the woofer and at the same time avoid overloads.

Also note that the overall colour of the sound depends on the ratio of the power of the subwoofer and the main speakers, especially at maximum volume. For example, if in one 100-watt 2.1 set the subwoofer has 50 watts, and in another — only 30 watts, then the first speaker at maximum power will produce richer bass, but with a lower volume of the main channels.

The frequency range that a subwoofer speaker can reproduce.

Recall that subwoofers are originally intended for bass frequencies. Therefore, the upper limit of the operating range in such speakers usually does not exceed 200 Hz — the main acoustic components can cope with higher frequencies; however, there are exceptions. Regarding the lower limit, it is worth recalling that for human hearing it is at a level of about 16 Hz. In modern subwoofers, the minimum reproducible frequency is usually somewhat higher — most often from 22 – 24 Hz; however, exceptions are possible here too — in particular, there are models with a lower limit of 13 Hz and even 8 Hz, that is, already at the level of infrasound. Such indicators are not only a sign of a high-class subwoofer — they also have a certain practical meaning, especially if the acoustics are used for a cinema. The fact is that many sound phenomena at low frequencies — explosions, earthquakes, etc. — are accompanied, among other things, by infrasonic vibrations that are not directly audible, but are still perceived by a person in one way or another .. Accordingly, a subwoofer with an extended infrasound range is able to convey such sounds as reliably as possible.

Impedance (dynamic resistance) of the complete speaker subwoofer.

This is relevant primarily for passive sets (see "Type"), where the subwoofer is also passive: knowing the impedance is necessary to effectively select an external power amplifier. Ideally, the resistance of the subwoofer should correspond to the resistance for which the corresponding output of the amplifier is designed — otherwise, either distortion and overload (if the subwoofer resistance is lower than optimal) or a decrease in volume (if it is higher) are possible.

In turn, for an active subwoofer, the impedance is mainly of reference value: the own amplifier of such a speaker, by definition, is optimally compatible with the speaker. However there is an opinion that a higher resistance reduces the level of interference and has a positive effect on the purity of the sound; however, the difference in impedance between different models is usually not so great that this effect is noticeable against the background of other factors that determine sound quality.

The presence in the design of the complete subwoofer AC adjustable crossover.

When it comes to low-frequency components, a crossover is a filter that determines the upper limit of the frequency range — it is understood that the main speakers are already responsible for sounds with a higher frequency. Accordingly, an adjustable crossover allows you to change this border and, accordingly, adjust the "division of duties" between the subwoofer and other components.

This function can be useful even in ready-made kits: depending on how much of the low frequencies are allocated to the subwoofer, the sound picture can change noticeably. And the ability to adjust will be especially useful if you plan to supplement the completed speaker system with third-party components in the future — for example, buy 3 speakers for a 2.1 model and assemble a full-fledged 5.1 multi-channel system. After all, adjusting the crossover is much easier than finding third-party speakers that are ideally suited for the range.

The ability to adjust the phase of the subwoofer supplied with the speakers.

This function is necessary because, in some situations, the audible sound from the subwoofer may be out of phase with the sound from the main speakers. Simply put, the sound waves from the subwoofer may be slightly ahead of the corresponding vibrations from the main speakers, or behind them. Such a situation may arise, for example, due to the difference in the distance to the individual components of the speaker, or due to the hardware features of the audio system; anyway, out of phase synchronization significantly degrades the quality of the audible sound. This adjustment allows you to correct the situation: it allows you to shift the sound of the subwoofer in a fraction of a second, achieving the most accurate synchronization.

The subwoofer has its own level control, in other words, a volume control. Adjusting the bass volume with such a control is usually much easier than digging into the settings of an amplifier or other signal source.

The presence of a complete subwoofer AC input LFE("low-frequency effect" — "low-frequency effects"). This interface is used in some multi-channel audio systems to connect a subwoofer. It differs from a regular subwoofer input in that a specialized signal is fed to the LFE, and not just the low-frequency part of the overall sound. This ensures a powerful and rich bass sound — including in the lower part of the range, at frequencies of the order of 20 Hz, where it is extremely difficult to ensure good audibility.

Note that not all subwoofers with this input have a separate connector for it — some models provide the ability to switch a regular line input to LFE mode.

Various additional features provided in the design of the column.

The list of such features may include general design nuances ( bipolar layout, magnetic shielding, horn design, Bi-Amping/Bi-Wiring, moisture protection), special types of emitters ( ribbon, electrostatic), adjustments to improve sound ( HF tuning, LF tuning, rotary tweeter), as well as special design elements to improve acoustic performance. Regarding the latter, it is worth noting that, in addition to the classic closed design, nowadays you can find sound system with bass reflexes( front, rear or bottom), acoustic labyrinths, passive radiators and acoustic spikes.

Here's a more detailed description of each of these features:

- Bipolar. Speakers of this design have two sets of emitters directed in different directions at an angle to each other (most often about 90° or slightly more). Such sound s...ystem are used in some specific cases - in particular, bipolar models are considered a good option for the rear channel in a home theater.

- Rotary tweeter. A tweeter is a high-frequency speaker that has a rotating design. This feature allows you to change the direction in which the speaker emits sound in the high-frequency range without rotating the body of the speaker itself (remember, the correct localization of such sound is quite important for adjusting the sound of the system as a whole). At the same time, there is no particular need to provide this function in stand-alone sound system: in such models, as a rule, there are no problems with rotating the entire body. Therefore, rotary tweeters are found exclusively in built-in speakers (see “Installation”) - after all, after installation, such a speaker no longer involves any movement.

— Magnetic shielding. In speakers with this feature, the housings are supplemented with special materials that are impenetrable to the magnetic field. Thanks to this, the powerful magnets that are usually equipped with speakers in modern speakers have virtually no effect on surrounding devices. This is especially important when used near sensitive electronics: plasma panels, high-end amplifiers and receivers, etc.

— Bass reflex. A device in the form of a characteristic tube installed in the column body with access to the surrounding space. The bass reflex (FI) amplifies the sound pressure and improves the sound of the speakers in comparison with similar closed-type sound system ; This is especially noticeable at low frequencies. True, the movement of air in the pipe can create additional noise; however, most models use various tricks to compensate for this phenomenon. But the clear disadvantage of such equipment is the increase in the overall dimensions of the column. We emphasize that this function should not be confused with an acoustic labyrinth (see below) - the FI is made straight and has a relatively short length.
We also note that the bass reflex can be installed in different ways: most often in the front, somewhat less often in the back, in some models - from below, and extremely rarely - from on top or from the side. And in some columns two FIs are installed at once, with different locations. These details are not indicated in the characteristics, since they can be easily determined from photographs. From an sound system point of view, it is impossible to say unequivocally which location is better - each option has its supporters and opponents, especially since the issue of sound quality is largely subjective. But from a purely practical point of view, the front FI is the most convenient: it allows you to place the speakers even close to the wall. When positioned in the rear, the speaker should be at a distance of at least 3–4 cm from the wall, and ideally at least at least the diameter of the bass reflex. The third popular option - installation from below - is found in certain models of bookshelf and floor-standing speakers equipped with stands of appropriate height, as well as in suspended models designed for a large amount of free space under the speaker.

— Acoustic labyrinth. Another device used to improve the richness and overall sound quality. In some ways similar to the bass reflex described on top, it is also an air duct of strictly selected length that connects the internal volume of the speaker with the external space. The key difference is that in this case the air duct is not made straight, but in the form of a “snake” with many bends (hence the name “labyrinth”). The walls of the labyrinth are covered with special materials that absorb sounds. This design has a number of advantages over traditional FIs. Thus, the speakers are more compact; with the same body dimensions, the labyrinth has a larger effective length, which has a positive effect on the power and saturation of low frequencies; and the winding air duct is almost not subject to the appearance of extraneous sounds (unlike bass reflexes, where in order to dampen such sounds it is necessary to very accurately calculate the design). On the other hand, labyrinths are noticeably more complex and, accordingly, more expensive, and therefore less common.

— HF adjustment. A control that allows you to adjust the sound level of high frequencies separately from the rest of the range. Due to this, you can change the color of the sound to a certain extent without resorting to external equalizers and other complex devices. This function can be combined with bass adjustment (see below), but there are also many speakers where only high frequencies are adjusted.

— Bass adjustment. A regulator that allows you to adjust the sound level of low frequencies separately from the rest of the range. Like the HF control described on top, it makes it possible to change the color of the sound to a certain extent without resorting to external equalizers and other complex devices. However, this function is very rarely used without a treble control (although such speakers also exist).

— Tape emitter. Ribbon-type emitter installed in one or more speakers; For a number of reasons, this design is used primarily in high-frequency tweeters. The difference between such devices and traditional emitters is that in this case, instead of a traditional coil, a metal strip is installed between the poles of the magnet (hence the name). This provides a number of advantages: high sensitivity, minimal distortion, wide horizontal coverage. The main disadvantages of the ribbon design are high cost and poor suitability for low frequencies.

— Electrostatic emitter. Electrostatic type emitter installed in one or more speakers. The design of such a device is based on a thin and light membrane, fixed between two stator grids - a signal is sent to the bottom, and the membrane vibrates with an electric field. In this way, you can achieve a very reliable, clean sound, with a minimum of nonlinear distortion. At the same time, electrostatic drivers are effective mainly at mid-high and high frequencies, so for effective operation the speaker inevitably has to be supplemented with traditional speakers. Among the obvious disadvantages of such equipment are the large dimensions, high cost and specific requirements for amplifiers: a radiator of this type requires a high-quality “amplifier”, always with an output transformer. Therefore, this function is rarely found - in some premium speakers.

— Horn design. The presence in the speakers of speakers built according to a horn circuit. Such a speaker has the appearance of a characteristic bell, in the depth of which there is an emitter. Due to their narrow directivity and specific influence on the propagation of sound waves, horns improve the efficiency of sound transmission over a fairly wide frequency range. In fact, we can say that the presence of a horn increases the sensitivity of the speaker. For a number of reasons, it has turned out that the horn design of the main speaker is used mainly in information speakers (see purpose), in other cases, this form is provided for the tweeter (tweeter).

— Passive emitter. The presence of a passive radiator in at least one speaker. Such a device can be described as a low-frequency speaker from which the coil and magnet have been removed, leaving only the outer membrane of the emitter. This membrane vibrates due to sound waves created by conventional speakers, and plays the role of a resonator, enhancing the sound of low frequencies. In this regard, a passive radiator is similar to a bass reflex and an acoustic labyrinth (see on top); at the same time, unlike FI, it is almost not subject to the appearance of extraneous noise, and costs significantly less than a labyrinth. On the other hand, an additional emitter on the front panel significantly increases the dimensions of the speaker - usually in height.

- IMAX Enhanced. The IMAX Enhanced Mark of Conformity is awarded to equipment that meets the audio certification requirements of IMAX Corporation. Combined with DTS audio technology to deliver signature IMAX theater-like sound in the home. The most accurate reproduction of such audio is possible in systems with a large number of channels (5.1 or more). Note that for a fully immersive experience, IMAX Enhanced certification must also apply to video equipment for playing content (TV, projector, etc.).

— Bi-Amping/Bi-Wiring. Possibility of operating sound system in Bi-Amping or Bi-Wiring format. Models with this feature are multi-band (see “Number of bands”) and have not one, but two sets of terminals for each speaker - for low and high frequencies. This allows you to use the mentioned connection methods. So, when working in the Bi-Wiring format, each contact at the output of the power amplifier is connected by two separate wires to two terminals on the corresponding speaker at once: for example, the positive contact of the left channel - to the positive contacts of the LF and HF inputs on the left speaker, the negative - to the corresponding negative contacts, etc. This allows you to improve the frequency response: thanks to the separation into separate cables, the low-frequency signal does not “steal energy” from the rest of the range, and each band receives enough power for the corresponding speakers to operate effectively. In the Bi-Amping format, two separate amplifiers are used, each with two pairs of output contacts - as a result, each speaker terminal is connected strictly to its “own” contact. This connection method is not cheap, but it allows you to achieve even greater sound purity and frequency response uniformity; Bi-Amping is considered the ideal option for tech who do not accept compromises in matters of sound quality.

— Moisture protection. The presence of special protection against moisture in the speaker design. This feature is highly desirable in three cases: if the system is planned to be used outdoors; if the indoor conditions are not very different from the outdoor ones (hangar, large garage, etc.); or if we are talking about a place with high humidity (swimming pool, greenhouse, some types of workshops, etc.). It is worth considering that the specific degree of moisture protection may vary - from the ability to withstand exposure to rain to the possibility of complete immersion under water; These details should be clarified separately.

— Acoustic spikes. Specially shaped supports, mainly used in floor-standing speakers. In accordance with the name, such supports are made pointed, and it is the sharp ends that rest on the floor; To protect the floor from damage, special small plates are usually used. In any case, the point of such a design is to minimize the contact area of the column with the surface underneath it. This, in turn, increases the pressure at the contact points and minimizes the so-called parasitic vibrations - vibrations transmitted from the speaker to the floor. Acoustic spikes are considered an almost mandatory element of equipment for Hi-Fi class floor-standing sound system - without such equipment, the mentioned parasitic vibrations can irreparably spoil the sound of high-quality speakers and negate all their advantages. Note that speaker spikes are also sold separately; however, buying sound system that were initially equipped with such stands is often easier than looking for third-party accessories.

Types of inputs provided in the design of the AU.

Note that the standard high-level terminal-based inputs used to connect passive acoustics to power amplifiers are not indicated in this list — their presence in the corresponding types of speakers is assumed by definition. The rest of the options could be:

— RCA. Inputs for working with analogue audio signal using RCA connectors (this connector can be used in other interfaces, but they have their own names). Usually, they are used in active systems and are designed for a line level signal, however, in some models, RCA is intended for connection to a power amplifier. In general, this interface does not differ in noise immunity, but its capabilities are quite enough at least for home acoustics, including quite advanced ones. Note that with this connection, each audio channel requires its own connector; therefore, RCA jacks are usually installed in pairs — stereo left and right.

— mini-Jack (3.5 mm). Standard connector for most modern portable audio equipment. The speakers are mainly used to connect similar equipment — primarily pocket media players. It uses analogue signal transmission, while the resistance to interference, like RCA, is not high, and the quality may even be lower due to the fact that both channels of stereo sound are transmitted over the same cable.

— Jack (6.35 mm)....A connector similar in shape to the mini-jack described above, but having a larger size; as a result, it is found mainly in stationary audio equipment, and is also used in musical instruments. 6.35 mm Jack is considered more durable and reliable than 3.5 mm mini-jack, besides, it is technically able to provide the so-called balanced connection (see below), although in fact this is rarely possible. To do this, this connector can be combined with an XLR connector (combo port), which allows you to connect one of the types of plugs of your choice.

— Balanced XLR. XLR connectors have three pins, according to the number of cable strands. They can be used to transmit a different type of signal, but in this case, an analogue balanced connection is implied. With this connection, one channel of audio is transmitted per connector, and a fairly large part of the interference that occurs during transmission is extinguished by the cable itself. The latter ensures the purity of the transmitted sound even at fairly large distances (of the order of several metres). Balanced XLR refers to professional interfaces and is found mainly in speakers of the corresponding class. Can be combined with a Jack (6.35 mm) connector (combo port), which allows you to connect one of the types of plugs of your choice.

— Balanced digital AES/EBU. A variation of the XLR interface, designed to transmit a signal in digital format. It also belongs to professional ones, uses the same connectors and cables and the same balanced transmission method, which ensures the cancellation of most interference; however, due to differences in the type of signal, it has a large bandwidth and allows even multi-channel audio to be transmitted through one connector.

— Optical. One of the varieties of the S / P-DIF standard is, along with the coaxial one described below. In this case, the signal is transmitted via a TOSLINK fibre optic cable. The main advantage of this interface is its complete insensitivity to electrical interference, while its capabilities are sufficient even to work with multi-channel audio. Among the shortcomings, it is worth noting the high price of connecting cables, as well as the need for careful handling of them.

— Coaxial. An electrical version of the S / P-DIF standard, using a coaxial cable with a “tulip” connector for signal transmission. Do not confuse this interface with the analogue RCA described above — despite the identity of the connectors, these standards are fundamentally different: "coaxial" works in digital format and even multi-channel audio can be transmitted over a single cable. Compared to optical S/P-DIF, this interface is less resistant to interference, but more reliable because electrical cables are not as delicate.

— Speakon. Professional interface used to connect the signal from the power amplifier to the speakers. It is used in the technique of the corresponding class, in particular, concert systems (see "Purpose"). Due to the features of the connectors (presence of latches, high degree of isolation) it can be used even with the most powerful amplifiers.

— USB port. The USB interface in speaker systems can have different purposes and use different types of connectors; these points should be clarified separately. So, one of the most popular formats for using this input is connecting speakers to the USB port of a PC or laptop to work as computer acoustics; models with this capability are equipped with USB Type B connectors — a characteristic square shape. Such acoustics will be useful, in particular, if the computer's specialized audio inputs are busy, out of order, or not available at all; in addition, it is often equipped with high-end built-in DACs and allows you to achieve higher sound quality than the average sound card.
There is another option — speakers with USB A inputs and built-in players that can independently play music from a flash drive or other external drive, as well as charge various gadgets like smartphones via USB.

Passive models (see "Type") are usually equipped with so-called high-level inputs designed for a signal from a power amplifier; this is a separate category of connectors installed in such models by default.

Types of outputs provided in the design of the speaker system.

Outputs in modern speakers are mainly used to switch the signal coming from an external source. However, other applications are also possible: for example, a speaker with a USB port (see "Inputs") and a built-in player may have connectors for connecting additional acoustics. The most common types of exits are:

— RCA. In this case, we mean an output for working with an analogue audio signal, usually a line level (an RCA connector can also be used in other interfaces, but they have their own names). In general, this interface does not differ in noise immunity, but its capabilities are quite enough at least for home acoustics, including quite advanced ones. Note that with this connection, each audio channel requires its own connector; therefore, RCA jacks are usually installed in pairs — stereo left and right. The exception is the subwoofer outputs, which can also be performed in this format — one connector is enough for them.

— mini-Jack (3.5 mm). Standard mini-jack socket. Most often used in the same way as RCA described above — for line-level analogue audio, including connecting subwoofers. At the same time, one 3.5 mm jack can be responsible for two stereo channels at once, however, the noise immunity of such an interface is even lower than that of RCA. Therefore, such a connector among the speakers is much less common.
Separately, we emph...asize that the headphone output (see below) is indicated separately, even if it also uses the mini-Jack jack.

— Jack (6.35 mm). A connector similar in shape to the mini-jack described above, but having a larger size; as a result, it is found mainly in stationary audio equipment, and is also used in musical instruments. 6.35 mm Jack is considered more durable and reliable than 3.5 mm mini-jack, besides technically it is able to provide the so-called balanced connection (see below), although in fact this possibility is relatively rare. One of the most popular uses for this output is connecting an additional speaker to a live speaker. Along with its younger brother, the 6.35 mm Jack connector can be used as a headphone output, but headphone jacks are not included in this category and are listed separately (see below).

— Headphones. Dedicated headphone output. Most modern "ears" have mini-Jack plugs (see above) — respectively, and this output is equipped with just such a connector. Occasionally there are speakers with Jack jacks, but this point is not important — a 3.5 mm plug can be connected to a 6.35 mm jack using a simple adapter (such adapters are even supplied with many headphones). Headphones can be useful, for example, at a later time of the day when loud music is undesirable — or vice versa, in a noisy environment, in order to hear the sound better; at the same time, the speaker is often closer to the listener than the player or other signal source, and it is most convenient to connect the “ears” to the speaker.

— Balanced XLR. XLR connectors have three pins, according to the number of cable strands. They can be used to transmit a different type of signal, however, in this case, an analogue balanced connection is implied. With this connection, one channel of audio is transmitted per connector, and a fairly large part of the interference that occurs during transmission is extinguished by the cable itself. The latter ensures the purity of the transmitted sound even at fairly large distances (of the order of several metres). Balanced XLR refers to professional interfaces and is found mainly in speakers of the corresponding class.

— Balanced digital AES/EBU. A variation of the XLR interface, designed to transmit a signal in digital format. It also belongs to professional ones, uses the same connectors and cables and the same balanced transmission method, which ensures the damping of most interference; however, due to differences in the type of signal, it has a large bandwidth and allows even multi-channel audio to be transmitted through one connector.

— Optical. One of the varieties of the S / P-DIF standard — along with the coaxial described below. In this case, the signal is transmitted via a TOSLINK fiber optic cable. The main advantage of this interface is its complete insensitivity to electrical interference, while its capabilities are sufficient even to work with multi-channel audio. Among the shortcomings, it is worth noting the high price of connecting cables, as well as the need for careful handling of them.

— Coaxial. An electrical version of the S / P-DIF standard, using a coaxial cable with a “tulip” connector for signal transmission. Do not confuse this interface with the analogue RCA described above — despite the identity of the connectors, these standards are fundamentally different: "coaxial" works in digital format and even multi-channel audio can be transmitted over a single cable. Compared to optical S/P-DIF, this interface is less resistant to interference, but more reliable because electrical cables are not as delicate.

— Speakon. A professional interface used to work with the signal coming from the power amplifier. It is used in the equipment of the corresponding class, in particular, concert systems (see "Purpose") — in this case, we are talking about connecting additional passive speakers to such a speaker. Thanks to the features of the connectors (presence of latches, high degree of isolation), the Speakon interface can be used even with the most powerful amplifiers.

The presence or specific version of the Bluetooth module installed in the speaker system.

The most common way to use such a module is to broadcast sound from smartphones, tablets, laptops and other Bluetooth devices to acoustics. The main convenience of such a connection is obvious — it is the absence of wires and the corresponding freedom of movement, especially since the Bluetooth range is usually at least 10 m (within line of sight). However, note that without special technologies, the audio signal during such a transmission is highly compressed, which affects the final sound quality; so aptX support is required to achieve good quality (see below).

In addition, Bluetooth can be used for other purposes; the most popular option for such an application in the AU is remote control from an external device. However, such features are much rarer.

As for different versions of Bluetooth, they differ both in terms of bandwidth and accessibility. Here is a description of the different options used in the AU.

• Bluetooth v2.0. The oldest of the versions found nowadays. Provides only basic capabilities and up to 2.1 Mbps communication speed, and is also much more prone to compatibility issues than newer standards. Therefore, this version can be found mainly among frankly outdated acoustics.
• Bluetooth v2.1. An updated version of the 2.0 standard, which received a number of improvements regarding the compatibility of...different types of devices and connection security. It is a kind of "classic of the genre", all newer generations of Bluetooth are basically v2.1 plus various additions and improvements.
• Bluetooth v3.0. A version in which a high-speed channel of 24 Mbps was added to the basic capabilities of Bluetooth 2.1 — for exchanging large amounts of data. At the same time, the Bluetooth module automatically determines the amount of transmitted information and selects which connection to use — regular or high-speed.
• Bluetooth v4.0. A fundamental update (after version 3.0), which introduced another data transfer format — Bluetooth Low Energy (LE). This protocol is designed mainly for miniature devices that transmit small amounts of information. Nevertheless, it allows you to significantly save energy when working with larger equipment, such as speakers — in particular, the energy costs for transmitting small service data packets are reduced.
• Bluetooth v 4.1. Development and improvement of Bluetooth 4.0. One of the key improvements was the optimization of collaboration with 4G LTE communication modules — so that Bluetooth and LTE do not interfere with each other. So if a 4G smartphone is often in close proximity to Bluetooth speakers, it is desirable that these speakers have a module with a version of at least 4.1. Another interesting innovation is the ability to simultaneously use a Bluetooth device in several roles (for example, to remotely control an external device while simultaneously streaming music to headphones). However, this point is more relevant for signal sources than for speakers.
• Bluetooth v4.2. Further, after 4.1, the development of the Bluetooth standard. It did not introduce fundamental updates, but received a number of improvements regarding reliability and noise immunity, as well as improved compatibility with the Internet of Things.
• Bluetooth v5.0. Version introduced in 2016. One of the key innovations was two special modes of operation of Bluetooth low energy: speed up mode (by reducing the range) and long range mode (by reducing the speed). In addition, a number of improvements have been introduced regarding the simultaneous operation with numerous connected devices.

A feature found in Bluetooth speakers (see above) and generally highly desirable for such acoustics.

aptX technology is designed to improve the quality of Bluetooth audio. Initially, the audio signal is heavily compressed during this transmission, and the sound quality can end up being quite poor. But in acoustics with the aptX codec, this drawback has been eliminated: this codec allows you to broadcast and receive sound in quality comparable to Audio CD — 16-bit / 44.1kHz. And although the actual sound quality of aptX is still somewhat inferior to the classic Audio CD with a wired connection, however, this point is most often not fundamental, and besides, the perception of sound is largely a subjective issue. Also note that in addition to the original aptX, a more advanced aptX HD can be used in modern technology — its capabilities are already being compared with Hi-Res audio 24-bit / 48kHz.

Of course, to use the appropriate codec, it must be supported by both acoustics and the signal source.

The presence of a remote control in the speaker package. Usually, this is a traditional IR remote control like those used in TVs.

The advantage of this feature is obvious: instead of having to go to the speaker every time to change the settings, it is enough to use the remote control. And some models with such an accessory in the kit are even equipped with built-in players and, in fact, are stand-alone music centers. The main disadvantage of remotes is the increase in the total cost of the speakers. In addition, additional control electronics is a potential source of interference, so such control is rarely used in Hi-End acoustics (although exceptions are possible).

The diameter of the tweeter (speakers) speakers. Since size primarily affects the range of the speaker (as the diameter increases, the operating frequencies decrease), in HF components it can be quite small. More detailed information can be found in special sources.

The diameter of the midrange speaker(s) speakers. The size of the speaker determines its operating range, as well as the total power: the larger the diameter, the lower the frequencies and the larger the radiating surface area (and hence the power). Accordingly, the dynamics for the midrange can be quite large, but in this case this parameter cannot be called critical. More detailed information can be found in special sources.

The diameter of the woofer or combined woofer/midrange speaker(s). The larger the speaker, the lower its operating frequencies and the more sound power it can provide. Therefore, you should pay special attention to this parameter if you want to get high-quality rich bass - especially if we are talking about an audio system without a subwoofer. More detailed information about speaker sizes can be found in special sources.

The diameter of the speaker (speakers) of the regular subwoofer speakers. This parameter is quite important for low-frequency components — it is on it that the ability of the subwoofer to produce powerful rich bass largely depends. It is believed that this requires a speaker of at least 200 mm in size; more detailed information can be found in special sources.

The material from which the cabinets of the speakers included in the speakers are made. Not only the appearance, but also the sound characteristics depend on this parameter. The most common options are:

— MDF(Medium Density Fiberboard — medium density fibreboard). The most popular material today, found in almost all price categories. At a rather low price, MDF has good acoustic characteristics, almost as good as natural wood.

— Tree. Wood can be classified as a premium material: it looks nicer than MDF, but in terms of acoustic properties it does not have significant advantages, but is noticeably more expensive. Because of this, this material is found mainly among high-end speakers designed for demanding users.

— Plastic. Plastic is low cost and easy to process. Its acoustic properties are worse than those of MDF and, moreover, wood; however, this shortcoming can be easily compensated for. So such cases are very popular nowadays, they are found even in high-end speakers.

— Metal. Most often, metal speaker cabinets are made of aluminium alloys. This provides an elegant appearance, in addition, such cases are very durable, reliable and are not afraid of scratches, dirt and moisture. On the other hand, metal is not cheap, and in some models it gives the sound a specific coloration that may not be to every...one's liking. To eliminate this effect, various design tricks can be applied, which, again, additionally affect the cost.

Note that for systems with a subwoofer (2.1, 5.1, etc., see “Number of channels”), this parameter specifies the material of the main speakers, while the subwoofer is in most cases made of MDF.

The wall thickness directly affects several characteristics. The first is the weight of the system. Thick walls add weight to the structure, which reduces the effects of vibration and sound distortion, resulting in a cleaner sound. The other side of the coin is the increased price. However, when it comes to sound quality, money cannot measure it here.

The total weight of all components of the speaker system.