Number of channels
— 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 speakers 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.Number of speakers
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.
Number of bands
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).
Impedance
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.
Front
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.
Total rated power
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.Overall frequency range
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.
Bluetooth
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.
Remote control
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).