Type
— Receiver. The key feature of the receivers, which distinguishes them from the players (see the relevant paragraph), is the presence of a built-in power amplifier that allows you to connect passive acoustics to the device. The design may provide other connection options — preamplifier output, digital audio jacks, etc.; moreover, the set of outputs in receivers is often more extensive than in the players. However, the main feature is precisely the compatibility with passive acoustics.
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Player. Devices for playing audio from various sources — from an external device that broadcasts an audio signal, from a USB drive, from files on a built-in storage device, etc. The only exception in this regard is content from local networks and the Internet: devices with such capabilities are usually referred to as a separate category —
network players(see below). The fundamental difference between the players and the receivers described above is the absence of a power amplifier. Thus, passive acoustics can only be connected to such devices through additional equipment.
— Network player. A variation of the players described above, capable of playing audio from network resources — streaming services (see below), computers and servers on the local network, etc. The specific set of network functions may be different, but they are necessarily available in one form or another. Also, many of these devices a
...re capable of working with non-network sources, such as external audio devices or flash drives; however, such functionality may not exist. All such nuances in each case should be clarified separately.Audio formats support
Audio file formats that the receiver is capable of working with. Among those, there may be lossy compressed (MP3, WMA, etc.), lossless compressed
Lossless(FLAC, APE, etc.) and
Uncompressed uncompressed formats (DSD, DXD, etc.).
In general, compression is used to reduce the volume of audio files. Lossy compression (the most common option) cuts off some of the audio frequencies (mainly those that are poorly perceived by the ear), making such files take up the least amount of space. Lossless compression preserves all original frequencies; this format is preferred by many lovers of high-quality sound, however, such files take up a lot of space, and the difference between normal compression and lossless compression becomes clearly noticeable only on high-quality equipment. Uncompressed formats, in turn, are intended primarily for professional audio work; their full reproduction requires Hi-End audio equipment, and the volumes of such materials are very large. However, these standards are quite popular among sophisticated audiophiles.
Separately, it is worth touching on
the uncompressed DSD format. This standard and its direct derivatives DSF and DFF use coding using the so-called pulse density modulation. It is considered more advanced than traditional pulse-frequency modulation, and allows you to achieve more accurate sound, a higher signal-to-noise ratio
...and less interference with a relatively simple element base.Streaming services
A set of
streaming services supported by the receiver.
Streaming (streaming) services are designed to broadcast content (in this case, mainly music) over the Internet. With such a broadcast, audio files are not saved on the receiver, but are played directly from the corresponding resource on the Internet; Nowadays, there are many such resources, varying in the range of music and access conditions. In any case, the main advantages of online streaming include a wide selection of content and almost instant access to the desired composition; Some services can also work like a radio, automatically selecting music according to the producer's preferences. Key resources include
Spotify,
TIDAL,
Qobuz,
Amazon Music.
Outputs
Outputs provided in the design of the device. Note that for receivers (see "Type") the presence of outputs for passive acoustics is mandatory by definition, and the players, on the contrary, do not have such outputs. Therefore, the presence / absence of such connectors is not separately indicated.
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Preamplifier output (Pre-Amp). A preamplifier is an electronic unit designed to amplify an audio signal to line level. Accordingly, outputs of this type are actually line outputs for outputting sound to an external power amplifier, active acoustics, etc. For players (see "Type"), these are the main analogue audio outputs, and in receivers, Pre-amp outputs can be used in including for connecting equipment that works in parallel with passive speakers, which provides additional features for expanding the audio system. Most often, this interface uses paired RCA connectors (“tulips”), one for each stereo sound channel; less often — balanced XLR, also paired, for more details see "Inputs".
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To the subwoofer. A separate output for connecting a subwoofer — a specialized speaker designed for low frequencies. Usually uses an RCA ("tulip") interface, but there may be other options. Anyway, this output receives the signal from the crossover, which "cuts" the mids and highs, leaving the bass with which the speaker works. This simplifies the connection and eliminates the need to look for external equipm
...ent for the normal operation of the subwoofer — for example, the same crossover (although an external amplifier may be needed for passive "subwoofers").
— Coaxial S/P-DIF. A kind of S/PDIF digital audio interface that uses an electrical coaxial cable with RCA connectors (“tulip”) for connection. Such a cable, unlike optical, is subject to electromagnetic interference to a certain extent, but is more reliable and does not require special care in handling. And the connection bandwidth is enough to transmit multi-channel audio up to 7.1. Note that, despite the identity of the connectors, the coaxial digital interface is not compatible with analogue RCA; and even cables for S / P-DIF are recommended to use specialized ones.
— Optical. A variation of the S/PDIF digital audio interface that uses a TOSLINK fiber optic cable connection. In terms of throughput, it is completely similar to the coaxial interface, but it compares favorably with its complete insensitivity to electromagnetic interference. On the other hand, due to their design, optical cables are sensitive to sharp bends and mechanical stress — for example, accidentally stepping on such a cable can damage it.
— Balanced digital (AES/EBU). An interface used primarily in professional audio equipment. It can use different types of connectors, but is most often implemented via XLR. For more information about this connector and the principle of balanced connection, see “Inputs — XLR (balanced)”, however, these two interfaces should not be confused: AES / EBU works with a digital signal transmitted over a single cable, regardless of the number of channels.
— Composite (video). This output is usually provided in models equipped with a video input of the same standard. For composite connectors in general, see "Inputs". Here also note that the role of composite audio outputs in this case is played by the main outputs of the receiver, to which acoustics are connected — in other words, the sound accompanying the video is output directly to the standard speakers of the audio system.
— BNC. Bayonet type connector used to connect coaxial cable. Theoretically, it can be used for various purposes, but in fact it is most often used similarly to coaxial S / P-DIF (see the relevant paragraph), for digital analogue audio. BNC connectors are more reliable in connection due to the bayonet lock; there is also a version with a threaded fixation.
— Trigger. The trigger output is used to automatically turn on other audio system components connected to the receiver. When the receiver itself is turned on, a control signal is sent to this output, which “wakes up” the connected device (for example, an amplifier) and relieves you of the need to turn it on manually. Of course, to use this function, the external device must be equipped with a trigger input.
— Control output (IR). The control output allows you to use the receiver's built-in IR receiver to control other components in your audio system from the remote control, such as an amplifier in another room, out of range of the remote control. With this scheme of operation, the audio receiver actually plays the role of a remote sensor, receiving commands and transmitting them through the control output to another device. Note that the very presence of such inputs and outputs does not guarantee the compatibility of various devices, especially if they are produced by different manufacturers; Sharing details should be clarified in the official documentation.Power consumption
The power consumed by the audio receiver during normal operation. Note that this parameter can be indicated in different ways: for example, some manufacturers measure it when the amplifier is operating at full power, while others measure it at 80% or 50% power. In addition, the power consumption of modern receivers is usually not so high as to put a serious strain on the power supply systems. Therefore, power consumption information usually plays a supporting role.
