Virtual surround sound
The projector supports
the virtual surround function.
The purpose of this feature is that due to special sound settings and the reflection of sound beams from the walls of the room, the listener hears more channels than are actually available in the projector (see "Audio Format"). For example, a 3.1 system with virtual surround sound can produce sound similar to 5.1 surround sound. This allows you to achieve the effect of "immersion" in sound without increasing the number of channels and the cost of the projector. On the other hand, the reliability of such sound is usually noticeably worse than that of real surround sound, and the overall quality is highly dependent on the characteristics of a particular room.
Note that the virtual surround function is specified for 2.0, 2.1, 3.0, 3.1 format systems. In more advanced multi-channel systems, there are a priori additional channels for reproducing surround sound.
Rated power
The total power rating of the sound projector speakers (including subwoofer, if present).
This parameter is often used to estimate the overall sound volume of the device, but this is not entirely true. The fact is that the actual sound volume is determined mainly by the power of the main speakers of the sound projector, and the total power is the sum of this power and the power of the subwoofer. Therefore, models with the same power rating can vary markedly in actual volume: for example, a 150-watt soundbar with a 50-watt subwoofer will be louder than a 100-watt projector with a subwoofer of the same power, although in both cases the rated power will be equal to 200 watts.
Summing up, we can say that it is possible to evaluate the volume by rated power only if the sound projector is not equipped with a subwoofer — in such models, the rated power is equal to the power of the main speakers. In other cases, it is worth focus on the power of the soundbar and the power of the subwoofer directly stated in the characteristics (see below for both).
Impedance
Impedance is the projector's resistance to alternating current, or more precisely, to the analog audio signal input from an external power amplifier. Actually, this parameter is of practical importance precisely if the device is planned to be used with an external amplifier. Ideally, the projector's impedance should match the impedance for which the amplifier is designed - otherwise, the volume may either decrease (if the impedance is too high), or distortion, overload, and even damage to the acoustics (if the impedance is too low) may occur.
Higher impedance is also thought to reduce the likelihood of interference. However, modern speakers (including sound projectors) have standard impedance values of 4, 6 or 8 ohms - the difference is not so great that the differences in sound quality are noticeable.
Acoustic design
Acoustic design of the subwoofer used by the sound projector.
— Closed type. The simplest design option is a speaker installed in a closed case. Such subwoofers have a relatively low volume, but are distinguished by good sound fidelity and a minimum of distortion.
— Bass-reflex type. Subwoofers equipped with a phase inverter - a special tube connecting the inner volume of the case with the outer space. Such equipment improves the volume and saturation of the sound, but increases the likelihood of interference (primarily the rumble of air in the pipe).
— With a passive radiator. The passive radiator is actually a speaker without a coil and a magnet, installed in the subwoofer cabinet along with the main speaker. The purpose of such a radiator is similar to the phase inverter described above, except that it is less susceptible to interference.
Inputs
—
USB A. In this case, we mean a USB connector that allows you to connect external drives (flash drives, hard drives) to the projector and play content directly from them. At the same time, models with video outputs (see below) can often work as a media centre, outputting the video signal to a TV or other external display.
—
mini-Jack (3.5 mm). By itself, the 3.5 mm plug can be used in different types of interfaces; in this case, it means a linear audio input with a mini-Jack socket. This input is mainly used to connect portable audio equipment (players, smartphones) to the sound projector.
—
RCA. Technically, RCA (colloquially "tulip") is a type of connector that can be used in different interfaces. However, the term "RCA input" is used to refer only to line inputs for connecting an analogue signal in stereo format. Note that this input consists of two sockets for RCA cables, because. Only one channel of sound can be transmitted through one cable.
—
Optical. Connector for digital audio signal connection via TOSLINK fibre optic cable. This interface allows for multi-channel audio transmission and is virtually immune to electrical interference; its disadvantage is the fragility of the cable.
—
Coaxial S / P-DIF. A connector for connecting a digital audio signal via an elect
...rical cable with an RCA connector (not to be confused with linear RCA, described above). Similar to the optical input described above, in particular, the ability to transmit multi-channel audio through a single connector. At the same time, a coaxial cable, on the one hand, is not so delicate, and on the other hand, it is sensitive to electrical interference (therefore, it is advisable to use a special shielded wire for such a connection).
— Composite. In this case, we do not mean a full-format composite interface of three connectors that allows you to transmit audio and video signals, but only one connector for working with video. And since sound projectors don't display images, the composite input is used to send video through the projector to another device, such as a TV. The composite video interface does not allow working with HD and is not of high quality; on the other hand, it is widespread and can even be used to work with frankly outdated video equipment. Typically this input uses a yellow RCA plug.
— Component. An input designed to receive an analogue video signal for further transmission to another device — a TV, video projector, etc. This connection typically uses three RCA connectors, each carrying a different video component (hence the name). Due to this, the component interface has good bandwidth and picture quality, it allows you to work with HD and is considered the most advanced modern analogue video standard.
— IR control input. Connector for connecting an external infrared remote control receiver. When properly placed, such a receiver will allow you to use the remote control even in places where the signal from the remote control cannot reach the main (built-in) sensor — for example, in another room. Note that the role of the receiver can be played not only by a specialized device, but also by another component of the audio system — for example, an amplifier with an IR control output.HDMI input
The number of
HDMI inputs in the design of the sound projector.
HDMI is the most popular modern interface for working with HD content, it allows you to transmit high-definition video simultaneously with multi-channel audio over a single cable. Having multiple inputs allows you to keep multiple signal sources connected to the projector at the same time and select the source from the remote without fiddling with reconnecting wires.
HDMI output
The number of
HDMI outputs in the design of the sound projector.
HDMI is the most popular modern interface for working with HD content, it allows you to transmit high-definition video simultaneously with multi-channel audio over a single cable. If you have multiple outputs, you can connect multiple signal receivers to the projector at the same time and switch between them from the remote control without touching the wires.
Number of speakers
The total number of speakers installed in the sound projector housing (external subwoofer is not taken into account in this calculation).
Given the same audio format (see above), more speakers typically provide greater fidelity and more precise localization of individual sound sources. This is especially true for models with virtual surround sound.
Control
The ability to control the soundbar, in addition to the standard push-button from the device case, also includes control from the
remote control,
the TV remote control to which the acoustics are connected, through the application
from a smartphone or tablet, and in some cases using a
voice assistant. More details about each of them:
— Remote control. The presence in the configuration of the classic remote control on IR sensors, like those used in TVs. It can contain much more settings functions than the controls on the body of the device and, of course, makes it easier to control the soundbar.
— TV remote control (HDMI-CEC). Connecting the soundbar via the HDMI port allows you to control it via the HDMI-CEC protocol via the TV remote control. This solution will reduce the number of remotes in the room and facilitate the comfort of the settings. However, the functionality of the "non-native" remote control may be limited. In this case, the compatibility of the TV and the soundbar can be achieved using other protocols (not necessarily HDMI-CEC).
— Smartphone control. The ability to control the soundbar through the application. This makes it easier to “search” for the remote control, because the phone is always at hand. The application also has extensive settings and such control is highly likely to be supported by t
...he TV, which allows you to execute absolutely any commands from your smartphone for a comfortable pastime on the TV.
— Voice assistant. This is not about the assistant built into the soundbar itself, but about compatibility with external devices that have this function (for example, with a smartphone or tablet). But even such compatibility allows you to give commands to the voice projector by voice — this is often more convenient than more traditional control methods. The specific set of supported commands and languages may vary depending on the voice assistant and its specific version. And among the most popular at the moment are Google Assistant, Apple Siri, Amazon Alexa.