Signal-to-noise ratio
The ratio of the level of the useful signal (the actual sound being reproduced) to the level of extraneous noise provided by the speaker amplifier in normal mode.
Any amplifier inevitably creates its own noise; You cannot get rid of them, but you can reduce their level. The higher the signal-to-noise ratio, the cleaner the sound will be, the less noticeable extraneous interference will be. However, it is worth keeping in mind that the signal-to-noise ratio is far from the only parameter that affects sound quality, and its high value does not guarantee pleasant sound from the speakers.
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.
More features
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LCD display. This screen makes device control more visual: it can display the operating mode, equalizer settings, battery charge level, etc.
— Handle/strap.
The presence of a handle or strap makes wearing the speaker more comfortable. So the handle is used mainly in large stereo speakers and makes them similar to boomboxes (
cassette recorders) of yesteryear. The strap can be used both for large speakers and for miniature ones, which allows you to hang them on your hand, on elements of a backpack, etc.
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Flashlight. This feature likely won't replace a high-end, dedicated flashlight. The power of the built-in flashlight is usually enough to illuminate at least a distance of 2 - 3 meters, and models with a bicycle mount (see above) can even play the role of a headlight (although, again, they are inferior to specialized bicycle lights).
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Carabiner/suspension A device in the form of a latch that allows you to attach the speaker to items of clothing, backpack straps, etc.
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Bicycle mount. A special device designed to mount the speaker on a bicycle, usually on the handlebars, at the user’s fingertips. Such models are often complemented by a hands-free function, which allows you to communicate on the phone without taking your hands off the
...steering wheel.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.