Comparison JBL Bar 2.1 vs LG SJ3

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 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 diameter of the speaker in the subwoofer used by the sound projector.

It is believed that the larger the speaker, the louder the sub and the deeper and richer sound it can provide. Models up to 200 mm in size are entry level; This is exactly the size that built-in subwoofers usually have (see above). But free-standing bass speakers can use larger speakers, up to 254 mm (10").

A decoder can be broadly described as a standard in which digital audio (often multi-channel) is recorded. For normal playback of such sound, it is necessary that the corresponding decoder is supported by the device. The first signs of multi-channel decoding were Dolby Digital and DTS, gradually improving and introducing new features. The final stage for 2020 is Dolby Atmos and DTS X decoders.

Dolby Atmos. A decoder that does not use a rigid distribution of sound across channels, but the processing of audio objects, due to which it can be used with almost any number of channels on a reproducing system - the sound will be divided between channels so that each audio object is heard as close as possible to its proper place. When using Dolby Atmos, in-ceiling speakers (or speakers facing the ceiling) are highly desirable. However, in extreme cases, you can do without them.

— DTS X. An analogue of the Dolby Atmos described above, when the sound is distributed not through individual channels, but through audio objects. The digital signal contains information about where (according to the director's intention) the object audible to the user should be and how it should move, and the processor of the reproducing device processes this information and determines exactly how the sound should be distributed over the available channels in order to achieve the required localization. Thanks to this, D...TS X is not tied to a specific number of audio channels - there can be as many as you like, the system will automatically divide the sound into them, achieving the desired sound. Also note that this decoder allows you to separately adjust the volume of dialogues. A separate variant of DTS X is the DTS Virtual:X decoder for providing surround sound without the use of additional upward speakers on the soundbar. You can rely on just two channels and a separate subwoofer to achieve the desired DTS Virtual:X effect. A separate variation of DTS X is the DTS Virtual:X decoder to provide surround sound without the need for additional upward-firing speakers on the soundbar. DTS Virtual:X can rely on just two channels and a separate subwoofer to achieve the desired effect.

— 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.).

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.

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.