Comparison Decker MDR-122 BT vs Sony CDX-GT500

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 pla...y 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".

— Android OS. Firmware based on Android OS significantly expands the capabilities of the radio, essentially turning it into a portable computer. Such firmware not only itself contains an extensive set of software, but also allows you to install additional applications for a wide variety of purposes. At the same time, unlike other devices running this OS, the ability to connect to the Internet for Android radios is far from mandatory - many models do not have Wi-Fi/3G/4G modules or 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 overall, but in this case there is no point in describing in detail the differences between the versions. The fact is that radio tape recorders often use highly modified editions of Android, and the differences between versions are often insignificant compared to the differences between specific editions, even within the same version. But what this parameter directly affects is compatibility with spe...cific software: many applications have restrictions based on the oldest version of Android on which they can be run. But we should not forget that at the time of release the device could have had one version of the OS, and at the time of sale it could have been updated to a more modern one.

- Windows CE 6.0. A special edition of the Windows operating system, designed for use in embedded and compact equipment, including car radios. In general specifications, it is similar to 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 standard radios (see “Mounting 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 vary, depending on the specific model. Most radios with such equipment are quite advanced devices with large color screens on which cards are clearly visible. Thus, the presence of GPS at least allows the device to work as a navigator. In addition, there may be other options for using this function, including quite specific ones - for example, adding coordinates to a video captured in DVR mode(see below) and even searching for nearby friends from social networks.

— DVR mode. The ability to use the radio as a DVR - more precisely, the main unit of the DVR, because To work, you will also need an external camera. In this mode, the radio tape recorder works for recording, recording the video captured by the camera onto a USB device, memory card or other drive. Such a video can be very useful in case of an incident on the road - for example, as evidence in a traffic accident case. As a rule, models with this function have some special features of full-fledged recorders - auto-start recording, cyclic recording, etc.

— Connecting parking sensors. The ability to connect parking sensors to the radio - a device that allows you to determine the distance to an obstacle in the car’s blind spot (for example, directly in front of the front and rear bumper). Parking sensors make parking and maneuvering in tight spaces much easier; It is often more convenient to display data from its sensors not on a separate internal unit, but on an existing radio.

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

— Wi-Fi module. The presence of a Wi-Fi wireless communication module in the car radio. This technology was originally created for creating 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. The ways to use this function in car radios may vary. Thus, some models support a classic communication to Wi-Fi access points to access the Internet - similar to how this is done in tablets. Others are able to connect directly, for example, to a smartphone for remote control and exchange of various data. And radio tape recorders with a 3G modem (see below) may even provide the ability to “distribute” mobile Internet to other Wi-Fi devices nearby.

- 3G ready. Possibility of connecting an external modem for 3G mobile networks to the radio. For more information about the 3G communication itself, see below; Let us note here that its support significantly affects the price of the entire device, although it is not always required. In light of this, radios are produced that are not equipped with their own 3G modem, but allow the communication of an external adapter. Such models are suitable for those who are not sure whether they will need a 3G communication: you can purchase a radio without overpaying for the built-in modem, and if necessary, purchase an adapter separately. However, it is worth considering 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 communication may be different, depending on the specific radio: listening to music and watching videos from the Internet, accessing cards 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 speed can be up to 70 Mbit/s (in practice, most often up to 10 - 15 Mbit/s), which is comparable to a fixed Internet communication. At the same time, the third generation is gradually being replaced by even faster 4G communications (see below), but for radio tape recorders, in most cases, 3G is sufficient (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 4th generation 4G LTE networks. The application 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 communication speeds - up to 173 Mbit/s, and in the future even higher. On the other hand, 4G networks are not yet as widespread as 3G, so before buying a radio with such a modem, it doesn’t hurt to make sure there is LTE coverage in your region.

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

— DAB radio. The radio can receive digital radio broadcasts. The main differences between such broadcasting and analogue (for example, FM) are high sound quality, almost complete absence of interference and extensive capabilities for transmitting additional information - text and even video. In addition, the signal quality does not deteriorate as the transmitter power decreases: the signal is either present in its pure form or not at all. It is worth considering that digital radio broadcasting is still much less common than analogue. In addition, in addition to the original DAB, there is an expanded DAB+ standard; Moreover, “plus” tuners are compatible with regular DAB broadcasting, but not vice versa. Therefore, before purchasing a device with this function, it would not hurt to check whether there is digital broadcasting in your region and whether the radio tuner is compatible with it.

- AirPlay support. The radio is compatible with AirPlay technology. This technology is used in portable Apple gadgets for wirelessly streaming 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. However, compared to another 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. The radio supports MirrorLink, a technology designed to connect smartphones to car multimedia systems. The idea of MirrorLink is that a mobile device runs various applications (for example, navigation or a player), and the driver and passengers can interact with them (control, receive information) through the on-board equipment of the car - a touch screen and a radio control panel, a remote control on steering wheel, etc. This technology is supported primarily by premium smartphones running Android.

- Dual Zone. This function allows you to use the radio to play two sound sources simultaneously, with one of them outputting to the front and the other to the rear speakers of the car's sound system. Thus, it is possible to separate to a certain extent 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 road conditions can be broadcast to the front seats. Volume adjustment is also carried out separately. The Dual Zone function will be useful primarily in minivans and other cars with spacious interiors, as well as in luxury cars.

- MHL support. MHL technology is used in portable devices to transmit digital audio and video signals through a universal connector such as microUSB or USB Type C; This eliminates the need for separate video outputs and has a positive effect on compactness. The bandwidth of this communication is similar to HDMI, it is sufficient even for HD resolutions. Specifically for a car radio, MHL support means that you can connect an MHL-compatible gadget to this model and take advantage of all the capabilities of this technology. And they include both video and audio broadcasting, 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, to work with MHL, you can use either a compatible HDMI port or another connector - for example, USB.

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 rated sound power produced by the radio amplifier for each audio channel.

Nominal is the highest average (rms) sound power at which the amplifier operates without overload and is able to operate for an unlimited time. This is the main indicator characterizing the overall sound volume of the radio; individual power surges can be much higher than the nominal value, but they are short-lived; here we are talking about a constant signal level. In addition, compatibility with specific speakers depends on this indicator: the rated power of the speaker system must be no lower than that of the amplifier, otherwise the speakers may be damaged at high volumes. 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 and more.

Optimal 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.

— 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.
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— 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 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 analog 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).

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).