Here, we need to understand a basic concept: decibel - the unit of sound pressure level (symbol: dB), for every doubling of sound pressure, the sound pressure level increases by 6 dB.
1 dB is the sound that the human ear can just hear; generally speaking, 15 dB or less we can consider it to belong to the " silent "; and 20 dB or less we consider it to be quiet.
20-40 dB is about the murmur of a couple's ear. Normal environmental noise intensity in 30-40dB, relatively quiet and comfortable; 40-60 dB belongs to our normal conversation sound, when more than 50dB (45dB at night) may affect sleep and rest, so that the normal physiological function is affected to a certain extent.
Above 60 dB is a noisy range, 70 dB we can consider it very noisy, interfering with normal conversation and communication, making people feel distracted and unfocused.
Above 90 dB (the upper limit of the national noise tolerance) will cause hearing damage and lead to other diseases, and stay in the space of 100-120 dB, if there is no accident, one minute humans will have to be temporarily deaf (deafening).
But there are cases where a high volume speaker is very necessary.
Do not forget that the above data is for normal people, for hearing problems in the population, such as the elderly, they have different needs. It is possible that what we generally consider as noisy sound is just right for them, so a smartphone with a good quality loud speaker can help them hear better.
For some people who work in a very noisy environment for a long time, such as construction workers, the surrounding environment may be more than 70 decibels, then if your phone volume does not reach this decibel or more, it is likely to cause you to not hear or hear clearly, so that you miss some important information or calls. Next, let's look at the results of a test done by GSMArena. Obviously, ordinary smartphones are not able to meet the needs of this group of people for the volume.
In addition, loudest speaker can have a broader use, for example, in the morning you have difficulty getting up, but you have to go to work, you have to go hunting, you have an appointment with friends to go out, especially in winter, wrapped in the blanket feeling really too cozy, ordinary alarm clock and can not wake you up, you begin to hesitate in the wake and continue to lie in bed, you begin to think about whether to change the plan, this time, At this time, if the ordinary alarm clock is replaced by a loud speaker, you will not hesitate to get up, as long as the sound is sounded, you are stimulated, you will quickly jump up from the bed to turn off the sound, this time your sleepiness is completely gone, maybe with the loud speaker, it will not become so difficult to get up.
In some extreme cases, smartphone with loudest speaker can even save your life, for example, you are trapped in a place, you need to shout for help, but your voice is too small, and only a few shouts, your throat is dumb, this time, with the power of the loud speaker, may be able to increase your chances of being rescued.
The smartphone with loud speaker is really practical, try to use the loud speaker phone to bring more surprises to your life.
