Car Stereos: specifications, types

— Automotive. Traditional car radios designed for use in car interiors, where the device will not be exposed to dust, precipitation and other adverse factors. They have typical mounting dimensions in whole DIN units; the exception is regular models (see below for both).

— Navigation. Radio tape recorders that allow installation on boats, yachts and other types of water transport. They differ from classic automobile models primarily in an increased degree of protection against moisture, temperature extremes and ultraviolet radiation — the cabins of boats and yachts are often made open, and such protection is indispensable. Note that many of these models also allow the use in the traditional way, in cars.

The size of the car radio in width and height, which determines the possibility of its installation in a car. For successful installation of the radio, it is necessary that the corresponding socket in the car has the same size as the radio itself, or more.

The universal unit for measuring the mounting dimension is DIN: 1 DIN corresponds to a width of 178 mm and a height of 50 mm. At the same time, devices of different sizes have the same width and differ only in height:

— 1/2 DIN. Compact devices with a height of 25 mm and a standard width of 178 mm.

— 1 DIN. The most common standard size of modern car radios (see dimensions above).

— 2 DIN. This standard size corresponds to a radio height of 100 mm and a width of 178 mm. Typically, 2 DIN sizes are quite powerful devices with a lot of additional features — for example, they are often equipped with large colour screens, suitable even for watching videos.

A separate variety are the so-called standard recorders. These are devices originally made for a certain brand of car and, usually, delivered immediately with them in one of the configurations. Such radios have their own unique mounting dimensions, often not related to the DIN standard, as a result of which they cannot be installed in any car models other than those for which they were originally intended. In addition, the instal...lation and dismantling of standard radios, usually, is much more difficult than that of universal ones. For more information, see head unit for.

Tape recorders with a shortened body,.

In this case, shortened means a case that has a shallower depth than classic radio tape recorders equipped with CD drives. Due to this, such models are quite compact, which, in particular, simplifies installation and facilitates wiring. Of course, CD / DVD discs are not supported in principle by such radio tape recorders, but this is not a serious drawback — nowadays there are quite enough alternatives to such media. Also note that the shortened layout does not affect the mounting size (see above) — it can be 1 DIN or 2 DIN, and standard solutions are even larger.

Car models for which this radio is standard.

For standard radios in general, see "Installation size" for more details. And here it’s worth saying that compatibility can be limited not only by a specific car model, but also by the year of manufacture — for example, “2015+” (that is, not earlier than 2015), “2012 — 2016”, etc. On the other hand, there are and softer restrictions — for example, the ability to install in several different models of the same manufacturer. Occasionally there is even the compatibility of one radio with cars of different brands — however, in this case we are usually talking about the availability of licensed copies of a certain car and, accordingly, the possibility of standard installation also in such copies.

Modern car radios can be produced, in particular, for cars of the following brands (in alphabetical order): Audi, BMW, Chevrolet, Chrysler, Citroen, Dodge, Ford, Honda, Hyundai, Jeep, KIA, Land Rover, Lexus, Mazda, Mercedes-Benz..., Mitsubishi, Nissan, Opel, Peugeot, Porsche, Renault, Seat, Skoda, Subaru, Suzuki, SsangYong, Toyota, Volkswagen, Volvo.

Design features of the front panel installed in the radio. Several features can be combined in one device at once — for example, a removable panel may well be folding.

— Removable panel. The ability to remove the front panel of the car radio and take it with you when leaving the car. The meaning of this function is to protect against theft: firstly, the front panel is the most accessible and attractive part of the radio for thieves; secondly, this reduces the likelihood of theft of the radio itself, as a device without a control panel is of little value.

— Folding panel. Control panel that can be folded forward, giving access to the front of the radio. This layout allows you to place the slot for loading optical discs not on the control panel, but behind it, thus saving space for additional keys on the panel itself. On the other hand, the flip panel is less convenient due to the fact that it must be opened and closed every time the disc is changed.

— Retractable screen. A retractable screen is usually reserved for premium radios. Such a screen, when folded, hides in the mounting socket of the radio in a horizontal position, and in the working position it slides out and becomes vertical. Thus, with the relatively small dimensions of the radio itself (see Mounting size), it can be equipped with a fairly large screen, which even allows you to co...mfortably watch the video.

— Motorized. This feature means that the display of the radio is equipped with a motor drive, due to which you can change the angle of the screen. This feature is especially important in light of the fact that in relatively inexpensive types of matrices, the image is normally visible only at a certain angle. However, the ability to adjust the tilt of the screen anyway may be useful.

— Tesla style. The front panel, made in the style of the on-board computer of Tesla cars. The main “feature” of this design is a huge by the standards of car radios (about 12 ") touch screen, from which not only the radio can be controlled, but also various functions of the car itself — for example, climate control. Accordingly, such radios have extensive capabilities. They they are usually standard (see "Head unit for"), while they are produced not only for Tesla, but also for other car brands.

Media types supported by the car radio.

— CDs. Support for optical discs usually assumes at least compatibility with CD, the ability to work with DVD is somewhat less common . For more information about these types, see "Disk Types". Here we note that nowadays, disks are gradually being replaced by more compact and functional media — in particular, memory cards and USB devices; so many modern radio tape recorders, including high-end ones, do not have optical drives at all.

— Memory cards. Ability to work with removable memory cards, usually SD or microSD; the module for reading them is called a card reader. This feature is convenient primarily because such cards are supported by many other devices — in particular, laptops and photo / video cameras. The card reader facilitates the exchange of data between these devices: for example, a selection of music from a laptop can be written to a memory card. Note that the specific type of supported cards needs to be specified separately — the (micro)SD format includes several varieties that are not quite compatible with each other.

— USB drive (front). The ability of the radio to work with external USB-drives — " flash drives ", hard drives, MP3 players, etc. — to play content directly from them. In this case, it means connecting such media to the USB connector located on the front panel of the radio — it is convenient because the connector is in close proximity, right at hand.

— USB drive (rear).... Connecting USB drives (see above) through the rear panel. However, the external device is connected not directly to the rear panel, but to an external USB connector, which, in turn, is connected to the rear panel with a cable. Such a connector does not take up space on the front panel, but you can place it on a shelf under the dashboard — and the connected drive will not stick out of the radio, but lie neatly on the shelf. But in standard radios (see above), the “rear” connection can be carried out a little differently — there the cable from the rear panel can be connected to the standard USB socket on the instrument panel using a special connector.

— Connecting an iPod/iPhone. The ability to connect portable devices from Apple to the radio — primarily iPods and iPhone smartphones — through a special docking connector. Even the simplest options for such a connection, in addition to playing music, provide a number of additional features — in particular, control of the player's functions (for example, switching a track) from the control panel or remote control of the radio itself. And the most advanced models have a proprietary CarPlay system; for more information about it, see "Control functions".

— Android connection. The ability to connect smartphones and other devices based on the Android operating system to the radio. Connection methods may vary: for example, some radio models support only a wired connection, others can use Bluetooth (see "Multimedia"). The same applies to the set of functions available in each case, this point should be clarified according to the manufacturer's official data. Specific features include direct playback of music from the phone (with control through the radio), working with the contents of its drive, watching videos, using the radio as a car kit for receiving calls, etc. And in high-end models, there is support for Android Auto smartphone integration technology; for more information about it, see "Control functions".

The maximum size of the memory card or USB stick (see "Media type") that the radio can work with normally.

High-capacity drives require fairly high processing power and may use special technologies that are not supported by all radios. This is the reason for the limitation on the volume of supported media.

Types of CDs (see "Types of media") that the radio can handle.

— CD. The most common type of optical disc; supported by all radios, where there are optical drives at all. CD capacity is relatively small — up to 700 MB, so many consider these media outdated. At the same time, this capacity is enough to record a music album (up to 80 minutes) in high-quality Audio CD format, or an entire discography in MP3 format. Therefore, such discs are still popular among music lovers.

— DVD. Optical discs of medium capacity, the heirs of the CDs described above. Allow you to record both music and movies in medium and even high (HD) resolution; the standard disk capacity is 4.7 GB. DVD support is relatively rare in car radios, mainly in the premium segment.

Note that compatibility with certain types of discs does not mean compatibility with all types of content for which these discs can be used. For example, a radio with a CD drive will not necessarily support MP3 (although models without support for this format are still very rare), and a device capable of reading DVD may not be able to cope with a movie recorded on such a disc.

Diagonal display size of car radio. The larger the screen, the larger the image on it and the better, usually, information is perceived; in addition, large size is important if the screen is touch-sensitive(see Touch screen). On the other hand, in car radios, the display size is limited by mounting dimensions and almost never exceeds seven inches.

Display size in dots (pixels) horizontally and vertically. The higher the resolution, the more detailed and smoothed the image is capable of producing the screen. High resolution is especially important for large diagonal displays; on the other hand, it significantly affects the cost of the device, and for a small screen it may even turn out to be superfluous (since the image will turn out to be too small).

The type of screen matrix installed in the radio.

This parameter is indicated mainly in cases where the screen uses a high-end IPS type matrix. This technology provides high colour quality, good brightness and wide viewing angles, and thanks to the improvement and reduction in price, the price of IPS screens is constantly decreasing. At the same time, it makes no sense to use this technology in a small display intended only for service information; therefore, the presence of an IPS matrix usually means a rather large screen, often a touch screen (see below).

Touch screen similar to those used in smartphones and tablets. Operating through such a screen is often more convenient and gives more options than using buttons and other classic controls. On the other hand, touch displays are quite expensive, they must be large enough (otherwise normal use will be impossible), and for relatively simple radio tape recorders, this function is redundant, more traditional control is quite enough for them. As a result, touch screens are used exclusively in advanced models with an abundance of additional features.

The presence of a special coating on the display of the radio tape recorder, which reduces the amount of glare from external light sources. None of the coatings can completely eliminate glare, but this feature anyway significantly improves image quality, especially in bright daylight.

— Android OS. The software firmware based on the Android OS significantly expands the capabilities of the radio, actually turning it into a portable computer. Such firmware not only contains an extensive set of software in itself, but also allows you to install additional applications for a very diverse purpose. At the same time, unlike other devices under this OS, the ability to connect to the Internet for Android radios is far from mandatory — many models have neither Wi-Fi / 3G / 4G modules, nor the ability to connect the appropriate adapters. But the presence of Bluetooth and/or GPS (see below), as well as a touch screen, is almost mandatory in such devices (although exceptions are possible here).
It is also worth noting that there are models on the market with different versions of Android ( Android 7, Android 8, Android 9, etc.). The newer the OS ( Android 10 or Android 11), the more advanced it is in general, but in this case it makes no sense to describe in detail the differences between versions. The fact is that heavily modified editions of Android are often used for radio tape recorders, and the differences between versions often turn out to be insignificant against the background of differences between specific editions, even within the same ve...rsion. But what this parameter directly affects is compatibility with specific software: many applications have restrictions on the oldest version of Android on which they can be run.

— Windows CE 6.0. A special edition of the Windows operating system, designed for use in built-in and compact technology — including car radios. In terms of general specifics, it is similar to the Android described above, but today it is outdated — official support was discontinued back in 2018. Therefore, models running this OS are rare and most often represent early models of regular radios (see "Installation size").

— GPS module. The built-in GPS satellite navigation module allows you to determine the current location of the device; but the further use of this data may be different, depending on the specific model. Most radio tape recorders with such equipment are quite advanced devices with large colour screens on which maps are clearly visible. Thus, the presence of GPS at least allows the device to work as a navigator. In addition, there may be other uses for this feature, including rather specific ones — for example, adding coordinates to a video captured in dash cam mode(see below) and even searching for nearby friends from social networks.

— TV tuner. Built-in module that allows the car radio to receive TV broadcasts; in other words, a device with this function is able to work as a TV (usually a TV tuner is combined with a fairly large display). However it is worth considering that broadcasting can be carried out in different ranges and formats (analogue, digital); therefore, before buying, it is worth clarifying whether the radio tape recorder supports exactly the desired type of broadcasting. In addition, you may need an external antenna for good reception.

— DVR mode. The ability to use the radio as a DVR — more precisely, the main unit of the DVR, because. You will also need an external camera to work. In this mode, the radio tape recorder works for recording, fixing the video that the camera shoots on a USB device, memory card or other storage device. Such a video can be very useful in case of an accident on the road — for example, as evidence in an accident case. Usually, models with this function have some special features of full-fledged recorders — auto-start shooting, loop recording, etc.

— Connecting parking sensors. Possibility of connecting to the radio radio parking sensors — a device that allows you to determine the distance to an obstacle in the blind zone of the car (for example, right in front of the front and rear bumpers). Parktronic greatly facilitates parking and manoeuvring in tight spaces; data from its sensors is often more convenient to output not to a separate indoor unit, but to an existing radio.

— Bluetooth. A technology designed for direct wireless communication between different devices. Can be used for different purposes. In car radios, the most popular options are, in particular: live audio streaming from a smartphone, tablet, etc. for car audio operation of the radio as an auto kit during a telephone conversation (when the subscriber's voice is broadcast through the same acoustics); remote control of the player on the connected device from the radio, etc. The specific functionality of Bluetooth depends on the model, it should be specified separately in each case.

— Wi-Fi ready. This feature means that the radio supports Wi-Fi (see below), but does not itself have its own Wi-Fi module — it must be purchased separately, in the form of an external adapter. This option is convenient because the user can buy a radio without overpaying for an "extra" wireless module, and then, if necessary, purchase a Wi-Fi adapter for it. However it is worth considering that such an adapter usually occupies a USB port, not allowing you to connect other devices to it.

— Wi-Fi module. The presence of a Wi-Fi wireless communication module in the car radio. This technology was originally created to create wireless computer networks (including for the purpose of connecting to the Internet), but recently it can also be used for direct communication of various devices with each other. How to use this function in car radios may be different. So, some models support the classic connection to Wi-Fi access points for accessing the Internet — similar to how it is done in tablets. Others are able to directly connect, for example, with a smartphone for remote control and exchange of various data. And in radio tape recorders with a 3G modem (see below), it may even be possible to “distribute” mobile Internet to other Wi-Fi devices nearby.

— 3G ready. Possibility to connect an external modem for 3G mobile networks to the radio. See below for details on the 3G connection itself; here we note that its support significantly affects the price of the entire device, despite the fact that it is not always required. Thus, radio tape recorders are produced that are not equipped with their own 3G modem, but allow the connection of an external adapter. Such models are suitable for those who are not sure whether they will need a 3G connection: you can purchase a radio without overpaying for the built-in modem, and if necessary, purchase an adapter separately. However note that an external modem usually occupies a USB port, which can create difficulties with connecting flash drives and other peripherals.

— 3G modem. Built-in mobile communication module designed for third generation 3G (UMTS) networks. The options for using such a connection may be different, depending on the specific radio: listening to music and watching videos from the Internet, accessing maps or map updates (in devices with GPS, see above), and in some models even voice calls and a full-fledged web surfing. The data transfer rate in this case can be up to 70 Mbps (in fact, most often up to 10 – 15 Mbps), which is comparable to a fixed Internet connection. At the same time, the third generation is gradually being replaced by an even faster 4G connection (see below), however, in most cases, 3G is enough for radio tape recorders (especially since such modems are relatively inexpensive).

— 4G ready. Radios with the ability to connect an external 4G adapter. Completely similar to the 3G ready models described above, except that in this case we are talking about 4G (LTE) communications; about it, see below.

— 4G (LTE) modem. Built-in mobile communication module designed for 4G LTE networks. By application, it is completely similar to the 3G modem described above (and can even work in 3G networks, in the absence of LTE coverage). The main difference is that 4G networks provide even higher connection speeds — up to 173 Mbps, and even higher in the future. On the other hand, 4G networks are not yet as common as 3G, so before buying a radio with such a modem, it's ok to make sure that there is LTE coverage in your area.

— NFC. Auxiliary wireless communication module with a short range (up to 10 cm). In car radios, it is mainly used to facilitate wireless connection with another device via Wi-Fi or Bluetooth: instead of setting up a connection, it is enough to bring an NFC-compatible device (for example, a smartphone or tablet) to the radio chip and confirm the connection. There are other ways to use this technology — for example, the automatic start of music playback from a smartphone when you bring it to the radio. However, such methods are less common, moreover, their set depends on the specific model of the radio and the capabilities of external devices.

— DAB radio. Possibility of reception by a radio tape recorder of digital radio broadcasting. The main differences between such broadcasting and analogue broadcasting (for example, the same FM) are high sound quality, almost complete absence of interference and extensive features for transmitting additional information — text and even video. In addition, the signal quality does not deteriorate when the transmitter power is reduced: the signal is either in its pure form, or it is not at all. Note that digital broadcasting is still much less common than analogue broadcasting. In addition, in addition to the original DAB, there is an extended DAB + standard; at the same time, "plus" tuners are also compatible with conventional DAB broadcasting, but not vice versa. Therefore, before buying a device with this function, it's ok to clarify whether there is digital broadcasting in your area and whether the radio tuner is compatible with it.

— Airplay support. Radio compatible with AirPlay technology. This technology is used in Apple portable gadgets to wirelessly stream music and video to external devices; accordingly, it makes sense to pay attention to models with this function if you plan to use the radio with an iPhone or other “apple” device. At the same time, compared to other proprietary Apple technology — CarPlay — this technology has more limited capabilities, it is intended exclusively for broadcasting content. On the other hand, AirPlay is much cheaper and can be provided even in relatively simple and inexpensive radios.

— Mirrorlink support. Support for MirrorLink, a technology designed to connect smartphones to in-car multimedia systems. The idea of MirrorLink is that various applications (for example, navigation or a player) work on a mobile device, and the driver and passengers can interact with them (control, receive information) through the car’s on-board equipment — a touch screen and a radio control panel, a control panel on steering wheel, etc. This technology is supported mainly by premium smartphones running Android.

— Fast charging. The function of accelerated charging of external devices — for example, smartphones — from the USB port of the radio. The general principle of this procedure is that the gadget is given increased power; but its specific features may be different. For example, some models provide a separate USB port designed only for fast charging, while others use the same connector that USB flash drives are connected to. In addition, special fast charging technologies can be supported in the radio; they speed up the process even more, but they only work with compatible devices; for other gadgets, accelerated charging may not be available at all. All these nuances do not hurt to clarify before buying.

— Dual zone. This function allows you to use the radio to play two sound sources at the same time, with the output of one of them to the front, and the other to the rear speakers of the car's sound system. Thus, to a certain extent, it is possible to separate what the driver and passenger will hear: for example, music or sound from a video player can be broadcast to the rear seats, and a radio broadcast with a news program or a report on traffic conditions can be broadcast to the front seats. Volume control is also carried out separately. The Dual Zone function will be useful primarily in minivans and other cars with large interiors, as well as in executive cars.

— MHL support. MHL technology is used in portable devices to transmit digital audio and video signals through a universal connector like microUSB or USB Type C; this eliminates the need for separate video outputs and has a positive effect on compactness. The bandwidth of such a connection is similar to HDMI, it is enough even for HD resolutions. Specifically, for a car radio, MHL support means that you can connect an MHL-compatible gadget to this model and use all the features of this technology. And they include both broadcasting video and audio, as well as additional functions — in particular, charging the gadget's battery and controlling it through the touch screen of the head unit. In the radio itself, both a compatible HDMI port and another connector, for example, USB, can be used to work with MHL.

The number of bands in the radio equalizer.

In this case, the band means a separate part of the frequency range, the volume of which can be adjusted using the equalizer independently of the other parts. The more bands the equalizer has, the more accurately it allows you to adjust the overall sound of the car radio acoustics. However, note that multi-band equalizers are quite difficult to set up, therefore they are recommended primarily for experienced users.

The number of fixed settings (presets) provided in the car radio equalizer.

The presence of such settings can greatly simplify the adjustment: choosing the right preset is easier than manually adjusting each EQ band. At the same time, presets are often selected by the manufacturer for certain genres of music and have the appropriate names — "Rock", "Pop", "Jazz", etc.; this simplifies the task even more. And the more fixed settings in the device, the wider the choice of the user. In some radio tape recorders, in addition to pre-flashed ones, user presets are also provided — they can be programmed in advance and turned on in the same way as the preset ones.

The ability to adjust the high cut without affecting other frequency ranges. Thanks to this, you can improve the overall timbre of the sound by completely removing the high frequencies, if necessary (for example, for a subwoofer). Moreover, this method of adjustment is much simpler than adjusting individual equalizer bands (see above). Typically, this function is combined with bass control (see below).

The ability to adjust the low cut without affecting other frequency ranges. Thanks to this, you can completely remove low frequencies (for example, for salon acoustics, when the subwoofer is “responsible” for the bass), without affecting other frequencies. This way of adjusting is much easier than adjusting individual EQ bands (see above).

A function that enhances the bass sound. In some way similar to the equalizer, however, unlike it, when using BassBoost, the bass boost is turned on and off with literally one touch of a button — this is more convenient and safer than fiddling with the equalizer settings.

The nominal power of the sound produced by the radio amplifier for each sound channel.

Rated is the highest average (rms) sound power at which the amplifier operates without overload and is able to work for an unlimited time. This is the main indicator that characterizes the overall volume of the sound of the radio; individual power surges can be much higher than the nominal value, but they are short-lived, but here we are talking about a constant signal level. In addition, compatibility with specific speakers depends on this indicator: the nominal power of the speaker system must not be lower than that of the amplifier, otherwise the speakers may be damaged at high volume. However, the spread is not so great, there are radios with an output power of 40 W, 45 W, 50 W, 55 W, 60 W or more.

Optimum amplifier power settings depend on a number of factors, ranging from the number of channels to the personal preferences of listeners. Detailed information on this topic can be found in special sources; in short, we can say that the higher the power per channel, the louder the sound the radio can produce.

The number of audio channels supported by the car radio.

The most modest value found in modern radio tape recorders is 2 channels. This is the minimum amount required to reproduce stereo sound, however, by the standards of car audio, it is considered modest and is found only in some low-cost-level devices. The most popular models are 4 channels — this format allows you to adjust the sound balance not only between the left and right channels, but also between the front and rear speakers. The best option for audio recorders. More channels are typical for high-end devices, usually equipped with large displays for viewing video ( VCR) and capable of working with multi-channel audio tracks.

The presence in the radio built-in DSP — digital sound processor.

Such a processor improves the overall sound quality and provides additional options for its adjustment. One of the most important DSP functions is time correction: it allows you to adjust the acoustics so that the sound from speakers located at different distances from the user reaches it at the same time. Such coordination significantly improves the impression of the sound. In addition, radios with DSP necessarily have a digital crossover (frequency separation) and an equalizer with a fairly large number of bands.

The presence of a processor significantly affects the price of the radio, but in most cases this is a justified payment for the sound quality. But the unequivocal disadvantage of "processor" models is the difficulty in installation and configuration, for this it is best to contact a specialist.

The bit depth of the digital-to-analogue converter installed in the car radio.

Such a converter (DAC) is responsible for "decoding" digital data (for example, an MP3 file) and converting them into an analogue signal, which eventually enters the speakers, turning into an audible sound. Bit depth is one of the characteristics that describe the quality of this conversion. However, it is worth noting here that there are two types of DACs — single-bit and multi-bit.

These types of DACs are fundamentally different in terms of signal processing, so only multi-bit modules can be compared with each other in bit depth. The standard values of this parameter, found in modern radio tape recorders with multi-bit converters, include 16, 20 and 24 bits; At the same time, the higher the bit depth, the more accurately the sound is transmitted. At the same time, we note that 16 bits is quite enough to reproduce sound in Audio CD quality. Therefore, it makes sense to specifically look for a radio tape recorder with high bit depth only if you want to equip a car with a Hi-Fi class audio system.

In turn, single-bit DACs provide quite acceptable sound quality, but in general they are inferior to multi-bit ones in terms of dynamics and sound purity. Such a converter is quite suitable for working with low-cost and mid-range acoustics, however, on high-end speakers, the difference in sound can be quite noticeable.

The type of volume control provided in the radio. Rotary knobs, sensors or mechanical buttons are most often used in this role; Here is a more detailed description of each of these options.

— Rotary regulator. The traditional regulator in the form of a round knob, which does not lose popularity nowadays — in fact, it is he who is installed in most modern car radios. Such prevalence, among other things, is due to the fact that the rotary knob is compatible with both digital and analogue volume control circuits — which means that it can be used in devices of any level, from top-end to the most simple and inexpensive. In addition, such a regulator stands out noticeably on the radio panel, so you can even find and turn it by touch, without being distracted once again from the road. The disadvantages of rotary knobs include perhaps some bulkiness compared to buttons and sensors, but this moment is extremely rarely significant.

— Mechanical buttons. Traditional mechanical buttons — more precisely, most often one double-sided rocker button, vertical or horizontal. Unlike the rotary knobs described above, they can only be used with digital volume control circuits; therefore, most radio tape recorders with buttons are advanced devices with extensive functionality and a size of at least 2DIN (or a screen of at least 5 ", for standard models). In such cases, the a...dvantage of buttons over rotary controls is that the rocker can be made very narrow and install even on a very thin screen frame, while the handle requires a fairly wide additional panel... And if you compare this option with sensors, then mechanical buttons are somewhat cheaper, and you can control them blindly without taking your eyes off the road to the radio panel. On the other hand, the mechanics tend to wear out with use, making it less reliable, and many users simply don't like buttons more than sensors, and for these reasons, and a few others, this option is relatively rare.

— Touch buttons. Controls in the form of sensors that are triggered not by pressing, but by touch. Like mechanical buttons (see above), this control is only compatible with digital volume control and is mainly used in advanced radios with large screens. At the same time, the sensors give the device the most advanced and “technological” appearance, attractive to many users from a purely aesthetic side. The main disadvantage of this option is that the touch buttons usually do not protrude from the panel — so it is almost impossible to find the right sensor blindly, and when controlling the radio, you inevitably have to be distracted from the road. However, with more or less decent driving skills and due care, this moment is not a serious drawback, so this type of control in high-end radio tape recorders is used much more often than traditional buttons.

— Remote control. The radio has a remote control. This function will be convenient primarily for passengers behind the driver — from the rear seats you can’t reach the radio itself. In addition, remotes often have more keys than the stock control panel, which allows you to access various additional functions on the go without digging through the settings.

— Remote control on the steering wheel. Remote control (see above) with the ability to mount on the steering wheel. Such a remote control allows the driver to control the functions of the radio without removing his hands from the steering wheel and thus not being distracted from driving the machine.

— Control from regular steering wheel buttons. The ability to control the radio from standard buttons, originally provided on the steering wheel for this very purpose. This function is similar to the steering wheel remote control described above, with the adjustment that the "remote" in this case is built directly into the steering wheel. Before buying such a radio, you must definitely check its compatibility with a particular model of car.

— Smartphone control. The presence of software (application) that allows you to control the radio using a smartphone, tablet, etc. This is not just about switching songs on the phone, but a full adjustment of all device functions....

— Voice control. The ability to control the radio using voice commands. The implementation of such control can be different: in some models, to activate it, you need to press a button, others constantly “listen” to the environment and immediately respond to code words. Anyway, this function allows the driver to control the radio without taking his eyes off the road, which has a positive effect on traffic safety. Note that in its pure form, voice control in modern radio tape recorders is becoming less and less common, being replaced by advanced technologies like CarPlay and Android Auto (see “Control Functions”), which also include voice functions.

— Apple CarPlay system. Support for car radio technology CarPlay. This technology is designed to connect portable devices from Apple to the radio, primarily the iPhone, although it is technically possible to work with any “apple” gadget that has iOS 7.1 or later firmware, as well as a proprietary 8-pin Lightning connector. Thanks to this technology, many smartphone functions (including the Siri voice assistant, navigation, call and message management, as well as music) are integrated into the radio; using them through on-board electronics can be much more convenient than holding the iPhone in your hands. At the same time, CarPlay puts special emphasis on safety: it is designed with the maximum use of voice control, so that the driver has to be distracted by the radio screen as little as possible. For example, the mentioned messages can be dictated by voice and listened to "performed" by Siri. The connection itself is carried out by wire, through the mentioned Lightning connector.

— Android Auto system. Car radio support for Android Auto technology. Similar to the CarPlay described above, this technology is designed to combine portable devices with on-board electronics of a car — only, as you might guess from the name, in this case we are talking about gadgets running the Android OS. When you connect such a gadget, the radio actually plays the role of an external display for a mobile device, with its optimized interface and related capabilities. Features available through Android Auto include navigation (including mobile device access to external GPS antennas and modules), music control, receiving and making calls, listening to and composing SMS, and searching the Internet. Android Auto is only available for Android 5.0 Lollipop and later; in addition, if the mobile device uses proprietary firmware, its compatibility with the radio needs to be specified separately.

The type of connectors used to connect an acoustic system (in other words, speakers) to the radio tape recorder.

— RCA. With this connection, tulip-type connectors are used to connect the radio and speakers; while each column has its own separate connector. Such an interface is quite difficult to connect, so it is relatively rare.

— ISO. The interface used to connect to the radio and acoustics, and power. It is a single plug to which all the corresponding wires are connected. Thus, the process of installing a radio with an ISO interface is as simple as possible: just connect the plug to the appropriate connector — and the device is ready for use. Most cars of recent years of production are equipped with an ISO connector, and if it is not available, you can buy and install such a connector separately.

— ISO/RCA. The main connection in such radios is carried out according to the ISO standard, and the RCA interface is used as an additional one — for example, to output to a subwoofer.

The number of line outputs (see above) provided in the design of the radio. It should be noted that usually these outputs use RCA connectors (“tulip”), and the analogue format allows only one audio channel to be transmitted through one such. Therefore, to work with a stereo signal, two RCA connectors are required, and just a pair of such jacks is considered to be one line output — a set designed for one set of stereo speakers. The main difference between this interface and the same RCA used to connect speakers (see above) is that the line output receives a signal from a preamplifier that is unsuitable for feeding to passive acoustics. Such a signal must be sent to active speakers or an external amplifier (whereas the speaker is connected to the output of a power amplifier designed for passive speakers).

The number of composite video outputs provided in the design of the radio.

The "full-size" composite interface includes 3 RCA ("tulip") sockets — one for the video signal and one each for the left and right stereo channels. However, other outputs are used in radios for transmitting an audio signal, so in this case we are talking only about the video output — usually it has a characteristic yellow colour. The video signal via the composite interface is transmitted in analogue format, its quality is average, resistance to interference is relatively low. At the same time, for connecting most car screens — for example, monitors built into the backs of the front seats — this is more than enough. And several composite outputs allow you to simultaneously connect the appropriate number of screens without the use of additional equipment (splitters).

A separate output for connecting a low-frequency speaker — a subwoofer. Ordinary speakers tend to have low quality bass reproduction; a subwoofer is used to “overlap” this range, as a result, the sound becomes much more powerful and rich. However, connecting to a regular audio output would require the use of frequency filters — so that only low frequencies enter the subwoofer. A separate output for the subwoofer eliminates the need for such devices — this connector is already filtered signal. However note that usually this interface is designed to connect an active subwoofer; passive will need a separate amplifier.

Additional outputs provided in the design of the radio and not related to those described above. These can be, in particular, such interfaces:

— Coaxial. Digital output for audio transmission (including multi-channel) via RCA cable, electric version of S/P-DIF interface. Do not confuse this standard with analogue RCA (see "Connecting speakers"): firstly, it uses a digital data transmission format; secondly, the entire signal is transmitted over one cable; thirdly, conventional RCA cables for coaxial connection are poorly suited, it is desirable to have shielded ones. Unlike optical S/P-DIF, this variant is subject to some degree of electrical interference; on the other hand, it does not require special care when handling the wire.

— Optical. A variation of S/P-DIF that uses a TOSLINK fibre optic cable to transmit the signal. Like the coaxial version described above, it supports multi-channel audio. At the same time, optical fibre, on the one hand, is completely immune to electrical interference, on the other hand, it requires rather delicate handling (in particular, it does not tolerate sharp bends).

— On the regular display. Output for connecting one or another regular display. This can be a screen that is originally installed on the dashboard of a car, or a monitor purchased separately; specific models of compatible screens should be specified in the documentation for the radio.

— High voltage. Speaker output with increased operating...voltage of 4V instead of the traditional 2V. This improves the signal-to-noise ratio and improves the overall sound quality. On the other hand, connecting speakers to such an output can be associated with additional difficulties.

Standard input for analogue audio transmission. The presence of such a connector allows you to connect an external sound source (for example, an audio player) to the radio to play music through the car's acoustics. The specific connector type used in such an input may vary. The same goes for its location; AUX on the front panel is most convenient, this feature is indicated separately in our catalog (see below).

The number of composite video inputs provided in the design of the radio.

Composite video input is usually an RCA connector ("tulip") of a characteristic yellow colour. It can be used to connect any video source with an appropriate output, such as a portable DVD player. Note that in this case, only the input intended for working with video is meant; to output sound, you will have to use another interface, for example, a linear one (see above). The image quality when connected via a composite connector is relatively low, HD resolutions are not supported, but this can hardly be called a serious drawback, given the characteristics of displays in modern radios (and separately made car TVs / monitors, which can broadcast a signal from the radio).

The more composite video inputs provided in the radio, the more signal sources can be connected to it simultaneously.

The presence of a line input (see Line input) directly on the front panel of the car radio. Such an input can also be located behind the panel (folding or removable), however, with its external location, it is much more convenient to connect external signal sources (for example, an MP3 player) to the radio, since this does not require folding or removing the front panel.

The presence of a separate entrance for connecting a rear view camera. In general, the ability to connect such a camera is useful in that you do not have to purchase a separate screen for it — you can use your own radio display, which is both cheaper and easier. Note that technically the image can also be received through another interface — for example, a composite video input (see above); however, the dedicated output is convenient in that it is synchronized with the camera being turned on. In fact, this means that you do not have to separately switch the input signal source on the radio — when you turn on the reverse gear and, in fact, the camera, the image from it will immediately be displayed. Shutdown is also automatic.

HDMI is a high-speed interface for transmitting high-definition (HD) video and multi-channel audio over a single cable. This is the most popular of these standards in modern video and audio technology, it is also used in portable devices, including tablets, cameras and camcorders, and even smartphones (sometimes in the form of MHL — see "Multimedia"). The presence of such an input allows you to broadcast video and audio signals from such devices to the radio.

Input for receiving analogue video signal in RGB format (“blue-green-red”, each colour has its own channel). To transmit such a signal, different types of interfaces can be used, but in car radios, a small plug of a round or oblong shape is most often found; the specific option should be clarified according to the official documentation. The RGB input is used most often to connect navigation modules.

Additional outputs provided in the design of the radio in addition to those described above. These are, usually, rather specific connectors that are rare, for example:

— Control bus input. Input for connecting the control bus — CAN, 5L-Bus, etc. The general idea of the control bus is to combine all the electronics of the car using the simplest single or double wire — instead of complex and bulky multi-wire bundles. Connection to the control bus allows, in particular, to display various data on the radio screen — speed, fuel consumption, tyre pressure, engine temperature, etc.

— Coaxial. Digital input for audio transmission (including multi-channel) through a single connector via an electrical coaxial cable. It is used to connect various advanced audio equipment.

— For the microphone. Input for connecting an external microphone. The microphone itself can be useful, for example, when using the radio as a car kit for a mobile phone, or for voice control. And the input for this accessory in different models can use different types of connectors, this point (as well as additional connection features) should be specified separately.

— For GPS antenna. Input for connecting an external GPS antenna. For more information about GPS navigation itself, see "Multimedia", here we note that an additional antenna provides more reliable reception, improving positioning accuracy and reducing the start time of the GPS receiver after a break in operation....r>
— For DVD changer. Service connector for connecting a DVD-changer — an external player for several DVD (or CD) discs. The presence of such an input allows not only to play music from the changer, but also to control its settings from the radio: switch between discs, manage playlists, etc. Note that the compatibility of the connector with a specific changer will not hurt to clarify separately.

— For Bluetooth-adapter. Input for connecting an external Bluetooth adapter. For more information about Bluetooth, see "Multimedia", here we note that in some radio tape recorders, instead of the built-in module, this option may be provided. It is convenient in cases where there is no certainty that Bluetooth will be needed in fact: you can buy a radio without overpaying for additional equipment, and purchase an adapter separately if necessary. However, note that the radio, usually, is compatible only with certain models of adapters; the list of compatible accessories in each case must be specified separately.

Audio file formats that the radio is capable of working with.

— FLAC. This format refers to the so-called lossless — that is, those that provide lossless compression. Music in FLAC retains almost all the smallest details of the original sound, but the files are several times larger than in MP3 or other lossy format. In addition, note that you can only appreciate all the advantages of FLAC on high-end audio equipment that is properly configured.

— A.P.E. Another lossless format. It differs from FLAC (see above), on the one hand, in a relatively small file size, on the other hand, in the increased requirements for the processing power of the player. Therefore, this lossless audio format is less common, mainly in high-end models.

— MP3. The most common popular format of modern music files, supported by almost all modern radios. Refers to standards that use the so-called lossy compression — when a certain part of the original audio is encoded in worse quality than the rest of the track. This reduces the file size, but slightly degrades the sound quality. At the same time, compression algorithms work in such a way that the degradation affects areas that are barely audible to the human ear; and with a sufficiently high bitrate and playback on average quality acoustics, MP3 can be practically indistinguishable from lossless formats (see below).

— WMA. Another format that use...s lossy compression. At the same time, the file size is somewhat smaller than in MP3, but WMA still does not have decisive advantages. At the same time, WMA and MP3 are so close that their support is often provided in parallel and is even written in the specifications as one item: "MP3 / WMA".

— AAC. A lossy compression standard similar to MP3, but used primarily on Apple devices.

Video formats supported by the radio.

Modern video files can include images of different resolutions (both low and HD), as well as different types of audio tracks, including multi-channel audio. From a practical point of view, the differences between the types of such files and formats are not so critical that each of them needs to be described in detail. However, in addition to this, certain types of physical media can also be attributed to video formats:

— DVD. For more information about DVDs themselves, see "Types of discs", and in this case it usually means support for Video DVDs — discs on which video is recorded in a specific way (with an on-screen menu, a table of contents, etc.). It is in this format that licensed DVD editions of various films and series are released, although if you wish, you can burn Video DVD on your own (unless you should not forget about copyright issues).

— VCD. Video CD is a standard similar to Video DVD described above, but intended, in accordance with the name, for ordinary CDs (see "Types of discs"). Today it is considered obsolete — in particular, due to lower image quality than Video DVD, as well as the inability to work with multi-channel sound. However, for a number of reasons, VCD support is still found in car radios.

— SVCD. A specific modification of the Video CD described above. Provides better image quality, but still inferior to Video DVD in terms of this indicator, and the original VCD in te...rms of the duration of video on one disc. Therefore, the SVCD standard itself has not received distribution, and its support in car radios is often a kind of “side effect” of universal disk drives.

— CDR, CDRW, DVDR, DVDRW. Ability to work with movies (and other content) stored on recordable and/or rewritable CDs and DVDs. Index R marks the recordable "blanks", RW — rewritable. Both types may differ slightly from factory-recorded media (such as licensed editions of Audio CDs and Video DVDs). These differences in most cases do not play a role, however, some manufacturers of radio tape recorders still indicate the possibility of working with "blanks" separately — most often for advertising purposes.

Anyway, before buying a radio, you should make sure that the video formats that you plan to watch are supported.

File formats supported by the car radio that are not related to audio and video (see above). Here are some of the most common such formats.

— JPEG. A popular graphic format used for a variety of images, from logos and screensavers to digital photography. In radio tape recorders, in addition to the above-mentioned screensavers, JPEG support can be useful for displaying cover art and other graphic materials on the display that complement the albums you are listening to, viewing photos from a digital camera, smartphone or tablet, etc.

— BMP. Graphic format similar to JPEG, but less common for a number of reasons.

— GIF. Graphic file format, the main feature of which is the ability to create animated images. At the same time, for still images, it is not as convenient as JPEG, and therefore is not as widely supported.

— txt. TXT files include plain text without any additional formatting. In radio tape recorders, this format can be useful, for example, for reading the text of a song being played or an electronic instruction for some accessory on the screen.

The volume of the internal built-in memory of the car radio. The presence of built-in memory allows you to record content (music, video, etc.) directly to the device and play it without using any additional media such as optical discs or USB drives. For comparison: the volume of a file with a photo is up to several megabytes, the size of one song in MP3 rarely exceeds 15 MB, the volume of lossless music files is estimated at tens of megabytes, and movies in DVD quality start from 1 GB. But for now (as of 2021), the memory in car radios is significantly inferior to smartphones and tablets — the bulk has 32 GB or 64 GB. But there are 128 GB radio tape recorders.

The amount of RAM memory.

Many modern premium car radios, as well as regular models, are close in functionality to tablets or even laptops; this is especially true for models that carry a full-fledged Android operating system on board. Accordingly, information about such devices may also contain purely "computer" characteristics, such as the amount of random access memory (RAM). The more “RAM” ( 4 GB or even 6 GB) provided in the system (ceteris paribus), the better it works under intensive loads, the easier it is to cope with “heavy” tasks (for example, resource-intensive applications) and performing several tasks simultaneously.

At the same time, note that manufacturers of radio tape recorders, usually, equip their devices with a volume of RAM that is quite sufficient for solving basic tasks and working with built-in programs ( 2 GB or less). Therefore, quite often information about the amount of RAM is more marketing than practically significant — it is designed primarily to create an appropriate impression of the product. It makes sense to pay attention to this characteristic if you plan to run various additional programs on the device.

It is also worth noting that different software platforms have different requirements for RAM, and the characteristics of the processor (see below) also affect the overall performance. Therefore, only model...s with similar processors and software can be compared with each other in terms of RAM.

The clock frequency of the processor (CPU) installed in the radio.

Many modern car radios (especially premium ones, with large displays and an abundance of additional functions, as well as regular models — see "Installation size") are actually multimedia computers. Therefore, their characteristics may indicate moments characteristic of computers — including the frequency of the processor. Theoretically, the higher this indicator — the more operations per second the CPU can perform and the higher its computing power. However, the actual speed of the processor depends on so many other factors that, compared to them, the clock speed is secondary; and it's not uncommon for a "slower" chip to be more powerful in fact. Do not forget that the capabilities of the entire system depend not only on the CPU, but also on the amount of RAM, the operating system used, and a number of other characteristics. And manufacturers usually select such processors that would allow radio tape recorders to cope with all the main tasks normally. In the light of all this, we can say that information about the frequency of the processor in fact has a purely reference and marketing (advertising) value.

— FM. This term refers to the part of the ultra-short wave (VHF) range ranging from 87.5 MHz to 108 MHz. It uses frequency modulation, which allows you to broadcast music in stereo with a fairly high sound quality, as well as transmit RDS signals (see RDS support). At the moment, most music radio stations in the CIS are broadcasting in this range. The disadvantage of FM is the limited reception area — a maximum of several tens of kilometers from the broadcasting station — so they can usually be listened to within the same city and surrounding areas.

— AM (English amplitude modulation — amplitude modulation) — broadcasting using amplitude modulation. It can be carried out in different bands, but most commercial broadcasts are carried out on medium waves in the range of 520-1610 kHz; most consumer AM receivers, including those in car radios, are designed for the same frequencies. AM broadcasting has a much longer reception range than FM (it can be hundreds of kilometers), but the sound quality is lower, so this format is broadcast mainly by “talk” and news radio stations.

— LW (English long wave) — broadcasting on long waves in the range of 148-408 kHz. Such broadcasting has a reception range of hundreds and even thousands of kilometers, and is almost independent of the time of day and atmospheric interference. It is used mainly at stations of national importance.

— MW (English medium wave) — broadcasting on medium waves in the range of 522-1720 kH...z, in fact — the same as AM (see above).

— SW (English short wave) — broadcasting on short waves, is carried out in a whole set of bands, the lower limit of which is at the level of 2.5 MHz, and the highest — 26.1 MHz. The features of the propagation of short waves are such that they can be received on the opposite side of the globe, but it is not always possible to hear within a few tens of kilometers from the transmitter. Therefore, shortwave broadcasting is mainly used for foreign broadcasts.

— VHF. In this case, not the entire VHF band is meant, but the sub-band 65.9-74 MHz, using the so-called OIRT modulation. In this format, VHF broadcasting was originally conducted in the countries of the Soviet Union and Eastern Europe, but at the moment it is not very popular due to the development of FM. VHF OIRT is technically similar to FM (see above); the main differences are the bandwidth occupied and the inability to transmit RDS signals in OIRT (see RDS support).

The presence of a USB port, the only purpose of which is to recharge gadgets. The USB port for charging eliminates the need for wires from the cigarette lighter, and using your smartphone as a navigator and simultaneously recharging it will be much easier.

The ability to choose the backlight colour for the control panel, and sometimes also for the radio display. The specific range of shades available can vary, whether it be a few colours or the entire RGB palette; see "Illumination colour" for details. Anyway, this feature does not play a functional role, however, it allows you to customize the appearance of the device so that it is in harmony with the appearance of the dashboard and matches the user's mood.

The colour of the backlight plays primarily an aesthetic role, allowing you to choose a radio for the design of the dashboard and user preferences. In addition, some colours have a practical meaning. So, the red backlight is extremely popular nowadays also because it is almost perfect for the dark time of the day: this shade does not knock down "night vision" and has a stimulating effect on the nervous system. And green, on the contrary, relieves excessive nervousness and promotes peace of mind. Other popular colours in modern times include white, blue, orange, yellow, purple ; they do not have such pronounced effects, here the main selection criterion is “like or dislike”.

Also note that in many models several backlight colours are indicated at once. This means that the device has a backlight with adjustable colour selection. At the same time, there are models with a choice of a full range of RGB colours.