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.
Output power
The total power of all channels of the speaker system. The higher the power, the larger the size of the room in which the audio system can be used, however, more
powerful portable speakers usually have larger dimensions and weight.
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.
Charging time
The time it takes to charge a fully discharged device to 100% charge.
Power bank mode
Ability to work portable acoustics in
power bank mode. This mode is only found in models with their own batteries (see "Power type"): it allows you to use this battery to power a smartphone or other external gadget. Thus, acoustics can play the role of an additional external battery, which is important in situations where it is not possible to charge a portable device in time.
Note that Power Bank speakers may only be compatible with certain phone models; this point should be clarified before buying.
