Comparison Alpine SPG-17CS vs Alpine SPG-17C2

— Broadband speakers. The simplest type of acoustics: one speaker is used to reproduce the entire frequency range. The advantages of such speakers are simplicity of design (as a result, low cost) and ease of installation. On the other hand, the sound quality of full range speakers is significantly lower than that of dedicated speakers (see below).

— Component speakers. The most advanced type of car speaker: it has separate speakers for each frequency band (see "Number of bands"), which allows you to customize the sound of each speaker as you wish and provide high sound quality. If the latter is the main factor for you when choosing car audio, you should pay attention to component speakers. However such systems are not cheap, and their installation can be quite complicated due to the large number of speakers.

— Coaxial speakers. A kind of compromise between component and full-range speakers: in such systems, small-sized tweeters and mid-range speakers are placed directly in front of the larger woofer cone, on the same axis with it. This design simplifies installation, reduces cost, and delivers better sound quality than full-range speakers. However this quality is still lower than that of component systems, and therefore “coaxials” are usually used either as rear speakers, or when for some reason (for example, due to cramped conditions) it is impossible to install a...component speaker.

— Cabinet speaker. The speakers of such acoustic systems are housed in a separate cabinet(s). This greatly simplifies installation — you do not have to find speakers to fit existing niches or even cut these niches on purpose, as in other types of speakers. On the other hand, such acoustics take up more space in the cabin.

— Midrange speakers. As the name implies, such a speaker reproduces only the middle frequency band, "cutting off" the highest and lowest. Technically, it can be used as a separate speaker, but this is usually not justified. Therefore, in fact, mid-frequency acoustics are usually installed as part of a more advanced component-type system (see above).

— Twitter. A speaker designed to reproduce high frequencies. Due to specialization, it is not used separately, it is used in combination with a mid-frequency speaker to build component-type systems (see above).

Rated power of the acoustic system. Most often, the average (root mean square) sound power is indicated as rated.

The most obvious point related to this characteristic is the volume of sound: the more powerful the sound system, the louder the sound it can produce, all other things being equal. In addition, compatibility with an external amplifier depends on this indicator: its power should not exceed the power of the sound system, otherwise overloads and damage to the speakers are possible.

The maximum power of a short-term (up to several seconds) incoming signal that the speaker can withstand without physical damage. Just like the nominal power, it matters for the selection of acoustics for an amplifier (or vice versa): it is believed that the maximum power of the speakers should be at least 2 times higher than the maximum power of the signal source.

This parameter determines the volume of the sound of a particular speaker when a certain standard signal is fed to it. Typically, this is considered a 1 W signal with a frequency of 1000 Hz. The higher the sensitivity, the less the speaker is demanding on the power of the amplifier. So, it is believed that for acoustics connected directly to the car radio, the sensitivity should be 80 dB or more; for less sensitive systems it is recommended to use a separate amplifier.

Crossover is part of acoustic system that divides the overall signal into separate frequency bands fed to the corresponding speakers (for more details, see "Bands"). All multi-band speakers (component and coaxial, see "Type") have their own crossover; it is usually located directly in the speaker body. However, in some models, usually the most advanced ones, the crossover can be made as a separate device, in its own body. External crossovers are considered to provide better sound quality and introduce less distortion into it; in addition, they often provide the ability to fine-tune the sound.

Size of the low-frequency speaker(s) provided in the speaker system.

This size is specified only for models with separate bass speakers. In such acoustics, it is the LF emitter that is the largest (this is due to the physical characteristics of the bass range). Accordingly, the space occupied by the entire system is determined mainly by the diameter of the LF speaker. And since the power and richness of the bass also directly depends on the size of the emitter, then when choosing, you have to proceed from a compromise between the capabilities of the acoustics and the available space in the car.