Front (RMS)
Rated output of one front channel of a home theater system. This paragraph indicates the power of the complete front speaker, however, it can also be used to determine the characteristics of the built-in amplifier — its rated power on a particular channel (not necessarily the front one), usually, slightly exceeds the power of the corresponding speaker.
Rated power in this case is the highest average (root mean square, RMS) sound power that the speaker is capable of delivering for an unlimited time, working without failures and overloads. Individual signal jumps can be stronger, but the power of acoustics is determined precisely by RMS.
The
higher this indicator(regardless of whether we are talking about front or some other speakers) — the louder the speakers, the better they are suitable for large rooms. At the same time, in a small room, too high power may be unnecessary, because. operating the speaker at full volume will cause discomfort — despite the fact that powerful acoustics also have the appropriate dimensions, weight and price. More detailed recommendations on the optimal power of the speaker components, depending on the characteristics of the situation, can be found in special sources.
Rear (RMS)
Rated output of one home theater rear channel. For more information about the meaning of this parameter, see "Front" above.
Centre (RMS)
Rated power of one centre channel of a home theater. For more information about the meaning of this parameter, see "Front" above.
Subwoofer (RMS)
Rated power of the subwoofer supplied with the home theater. See "Front" above for details on power rating; here we note that subwoofers often have a fairly high power, because. they are designed to cover low frequencies in all audio channels.
Total power (RMS)
The total power rating of all home theater speakers, including subwoofers. The value of the rated power is described in detail in paragraph "Front" above.
Frequency range
The range of audio frequencies reproduced by a home theater speaker system. The wider the range — the richer the sound, the less likely it is that the acoustics will “cut off” part of the low or high frequencies. When evaluating this indicator, one should proceed from the fact that the range perceived by the average human ear is from 16 Hz to 20 kHz. However, modern home cinemas for the most part cover this range completely or almost completely.
Impedance
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.
Amplifier frequency range
The range of audio frequencies that the built-in home theater amplifier can produce. This indicator is similar to the speaker range described above: the wider it is, the more part of the sound is covered by the device, the less high and low frequencies are outside the operating range. At the same time, it is worth noting that the frequency range of the amplifier, usually, corresponds to the capabilities of the complete speakers. Therefore, usually, you have to pay attention to this parameter only when connecting "non-native" acoustics: it is desirable that its range is not narrower than that of the amplifier, otherwise the latter will not be able to realize all its capabilities.
Other file formats
Non-video file formats supported by the home theater (see above).
— MP3/WMA. One of the most common music file formats. They are two separate types of digital audio, but in many practical aspects they are so similar that it is technically easy to provide simultaneous support for MP3 and WMA, and in most modern home theaters one is not separated from the other. They belong to formats that provide the so-called lossy compression (lossy) — the file size is small, but this is achieved by deteriorating the accuracy of sound transmission in certain sections of the track. However, these sections are chosen in such a way that the deterioration is almost inaudible, and at a high bitrate, the sound in MP3 or WMA is almost indistinguishable from FLAC (see below) and other lossless formats.
— Audio CD. An ordinary, familiar to everyone and ubiquitous music disc, usually containing about 15-20 tracks (up to 80 minutes of sound). Universal, supported by absolutely all devices capable of reading optical media, regardless of the year of their release. At the same time, the sound quality of Audio CD is so high that it is sufficient even for Hi-Fi level equipment. Due to this, and also due to the low cost, such media are still widely used, despite the emergence of more advanced options.
— Audio DVD. A format similar to Audio CD, but designed for DVD discs and designed specifically for the storage and high-quality reproduction of audio information. In this format,...you can record sound with a different number of channels, up to 5.1. It has not received wide popularity, although it enjoys a certain popularity — in particular, due to the higher sound quality than on Audio CDs (which are quite good in themselves).
— Super Audio CD. An improved version of a regular Audio CD that exceeds its sampling rate by 64 times, thereby providing a higher sound quality. SACD discs are not compatible with conventional CD drives (at best, it is possible to play the so-called "hybrid disc" as a normal Audio CD); therefore, to work with media of this type, it is worth choosing devices in which support for Super Audio CD is directly claimed.
— JPEG. The most common modern graphic file format is, in particular, the standard in digital photography. Therefore, if you intend to use your home theater to view photos, you should choose a model with JPEG support.
These are the most common additional formats. In addition to them, modern home theaters can support other types of files, for example:
— AAC. An audio format similar to MP3 and WMA, but primarily used by Apple technology.
— GIF. Graphic format primarily used for creating animated images.
— FLAC. An audio standard that provides lossless compression, one of the most popular lossless audio formats today. Provides higher fidelity sound transmission than MP3 and the like, but the file size is many times larger.
— A.P.E. Another lossless compression standard. The size of APE files is smaller than FLAC, but this requires quite a lot of processing power from the playback device. Therefore, support for this format is somewhat less common.
— txt. Text storage format. Working with such files can be useful, for example, to view the text of a song being played from a disc on a TV screen.
— SRT, SUB, ASS. Popular external subtitle formats. They differ in functional features: for example, SRT allows you to work only with unformatted text, while ASS supports various fonts, colours, effects, etc. However, the essence of such files is the same — the addition of video files with subtitles.
