Passive emitter
The presence of a
passive radiator in the design of the speaker system.
Such an emitter is a speaker cone that does not have its own coil and magnet — in other words, it does not produce sound itself, but only vibrates from the sound of other speakers. Like the phase inverter (see above), this part is intended to improve sound pressure and sound depth, especially at low frequencies; at the same time, the advantage of a passive radiator is the absence of a tube, due to which the design is simpler and more compact than with a phase inverter.
Frequency range
The range of audio frequencies reproduced by the audio system. The wider the range, the richer the sound, the more details the speakers can convey, especially in the low and high frequencies. At the same time, we note that the average human ear is able to hear sounds in the range of about 16 – 20,000 Hz, and it makes no sense to provide a wider range in speakers — a person simply will not hear it. Also note that a wide frequency range alone does not guarantee good sound quality.
Battery capacity
Theoretically, a
higher capacity allows to achieve greater battery life, but in fact, the operating time also depends on the power consumption of acoustics — and it can be very different, depending on the characteristics and design features. So this parameter is secondary, and when choosing it is worth paying attention not so much to the battery capacity, but to the directly claimed operating time (see below).
Battery life
Operating time of a portable audio system without connecting to an external power source (network or USB port, depending on the capabilities). Note that manufacturers tend to indicate battery life in their specifications under optimal conditions for energy saving: at low volume, without using additional functions, etc. Therefore, in fact, this indicator may be noticeably lower than the claimed one, and
speakers with a long operating time will not sound at full volume for the specified hours.
Waterproof
The presence in the design of the acoustics of
a protected housing that prevents dust and moisture from entering the sensitive electronic filling. The specific degree of such protection in different models may be different — some speakers are able to endure even complete immersion under water (
waterproof), others are designed only for exposure to moderate rain. Therefore, the specifics of the protected case should be clarified separately according to the manufacturer's official data. However, anyway, such speakers will be more resistant to bad weather and better suited for outdoor use than those that do not have dust and water protection; therefore, if you are choosing acoustics for outdoor trips, it makes sense to pay attention to models with this function.
Some models with this feature are officially IP certified. The IP index includes two digits — for example, IP54. The first digit indicates the degree of protection against dust, the second — from moisture; the higher the number, the higher the corresponding degree of protection, detailed data can be found in special sources.
