Comparison Sony HT-RT4 vs Sony HT-RT3

Home theater speaker system AC impedance. Impedance matters when connected to an amplifier: if the impedance of the speaker system is less than that of the amplifier, distortion in sound is possible, if it is higher, the acoustics may sound quieter than we would like. Naturally, in the original home theater sets, the speakers and amplifier are selected with the optimal impedance ratio, so in fact you only have to pay attention to this parameter when you need to connect acoustics to a “non-native” amplifier.

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. Dolby Digital and DTS were the first signs of multi-channel decoding, 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.

— S video. An analogue connector is most often used to receive a signal to a home theater from a computer or camcorder, although it can be used with any other signal source equipped with an appropriate output. The connection uses one cable and one connector, but the signal is transmitted through two separate wires, due to which S-Video outperforms the composite interface in terms of image quality and resistance to interference, although it is inferior to the component one (for more information about these interfaces, see "Outputs").

— USB input. A classic USB connector used to connect various peripherals. In home theaters, it is most often designed to connect external drives — "flash drives", hard drives — and play the files recorded on them. Also, such drives can be used to update the firmware. Anyway, this function greatly simplifies the exchange of information between the theater player and the computer.

— Coaxial. Input for digital audio transmission via RCA connector ("tulip") and the appropriate cable. However, a regular RCA cable is not suitable for such a connection; it is advisable to use a shielded one; this is the main difference between a coaxial interface and an analogue interface with the same connectors. Another difference is that all sound channels (there may be more than two) are transmitted via one connector. The coaxial interface formall...y belongs to the S/P-DIF standard; from another variety — optical (see below) — it differs in two ways: on the one hand, lower resistance to interference, on the other, a less delicate and fragile cable.

— Linear. Input for analogue audio transmission, usually in stereo format. Through such an input, you can connect an external signal source to the home theater — for example, an MP3 player — and listen to music through the acoustics of the cinema. Despite the development of digital technologies, the line-in is still one of the most popular connection interfaces. It can use different types of connectors; the most popular options are 3.5 mm mini-jack or a pair of RCA jacks (one for each stereo channel).

— Optical. Digital input for high quality sound transmission, including multichannel. The optical connection is notable for its complete insensitivity to electrical interference. On the other hand, the TOSLINK cable used for such a connection is quite delicate and can break if sharply bent or crumble under strong pressure.

— LAN (RJ45). It's a network port. Allows you to connect your home theater to a local computer network and access content stored on computers on this network, and if you have the appropriate capabilities, also access the Internet (both for watching video and listening to audio online, and for service purposes, such as updating firmware). However a wired connection is less convenient than Wi-Fi (see "Multimedia"), due to the presence of the wire itself. On the other hand, it provides higher actual data transfer rates, and also allows you to “offload the air” — to remove part of the load from the Wi-Fi router, to which, in addition to the cinema, many other devices (mobile phones, laptops, etc.) can be connected. .).

— Under the microphone. Standard input for connecting an external microphone. The presence of such an input is mandatory for players with a karaoke function (see Karaoke).