Number of fixed settings
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.
DSP
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.
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).
Fast charge
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 increased power is supplied to the gadget; but its specific features may be different. For example, some models provide a separate USB port intended only for fast charging, while others use the same connector to which flash drives are connected. In addition, the radio may support special
fast charging technologies; they speed up the process even more, but only work with compatible devices; for other gadgets, accelerated charging may not be available at all. It doesn’t hurt to clarify all these nuances before purchasing.