Resolution
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).
Screen type
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).
High Pass Filter (HPF)
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).
Low Pass Filter (LPF)
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).
Bass Boost function
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.
Power per channel
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.
Volume control
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 advant
...age 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.Line out
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).
Video input (composite)
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 color. 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.
