Comparison JBL Bar 2.1 vs Harman Kardon SB 20

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.

The nominal power of the speakers installed directly in the soundbar, excluding the subwoofer (in models with a built-in subwoofer, respectively, only the power of the main speakers is taken into account).

This indicator directly determines the overall volume of the sound projector; It is worth choosing according to this parameter taking into account the specifics of the room in which the projector is planned to be installed: the larger the room and the greater the distance to the viewer, the higher the power should be, otherwise the soundbar will not be able to effectively sound the scene. Detailed recommendations on the optimal power for different situations can be found in special sources.

The audio frequency range supported by the projector's speakers.

When evaluating this parameter, it is worth remembering that the audibility range of the human ear is about 16 – 22,000 Hz (and narrows with age). If the projector's frequency range is narrower, this can result in "cutting" low or high frequencies (however, with a slight narrowing, this effect is almost imperceptible). There are models in which the frequency limit is much wider — however, this is a kind of "side effect" of high-quality acoustics and has no meaning other than advertising.

Also note that a wide frequency range in itself does not guarantee high-quality sound — a lot depends on other parameters of the projector.

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.

The sensitivity value determines the volume of the projector when a signal of a certain power is applied to it. Given the same input power and impedance, a more sensitive system will produce higher volume.

This parameter is important primarily when operating the projector with an external amplifier. At the same time, models with values up to 88 dB are considered low sensitivity, 88 – 92 dB are considered medium, and more than 92 dB are considered high sensitivity.

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.

The rated power of the subwoofer included in the design or delivery of the sound projector.

The higher the power, the louder the sub can sound, the richer the bass it can provide. On the other hand, an increase in power inevitably promises an increase in the size and cost of the speaker. Therefore, an overly powerful subwoofer is just as undesirable as one that is too weak. Detailed recommendations for selecting power for the size and acoustic characteristics of a particular room can be found in special sources.

Note that the external subwoofer in soundbars should be approximately twice as powerful as the soundbar in order to prevent sound sags at maximum volume. So, if the total output power of the speaker system is 300 watts, then 100 of them should come from the soundbar alone, and 200 should go directly to the subwoofer.

— 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.

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.