Three powers of earphone speakers
There are three types of speaker power: one is the maximum allowable power, which refers to the input electric power that the speaker can withstand in a short time without being damaged; the other is the maximum instantaneous power, which refers to when the speaker's harmonic distortion is less than a specified value Input electric power (the distortion degree greatly exceeds the rated distortion degree of the speaker); there is also a rated power, which refers to the input electric power that the speaker works for a long time without being damaged.
For a long time, the rated power has been used in most speaker manuals to indicate its power endurance, and the rated power is doubled as the maximum power endurance of the speaker. The so-called rated power is expressed by the effective value power of the continuous sine wave, which is generally called RMS (that is, the root mean square power of the sine wave). Since the difference between the peak value of the sine wave and the effective value, that is, the "peak adjustment" is only 3dB, this method completely eliminates the influence of the short-term peak signal component of the program that is 10dB higher than the average value on the speaker, so it can be higher. The rated power data of, and double this data as the maximum withstand power.
This kind of test only adds 1 hour of sine wave signal to the loudspeaker, which is obviously improper. The key is that it cannot truly simulate the musicality and sudden peak characteristics of the actual program. However, this method has been widely adopted in the past and is still adopted by manufacturers.
An important issue in the calculation of speaker power is the power bandwidth. Usually the speaker system has a rated frequency response range, such as from 50Hz-18kHz. Then, if the working frequency of the speaker system is lower than its rated lower limit, the power it can withstand will be greatly reduced. For example, a speaker with a lower limit frequency of 60Hz, with a continuous power of 200W for a long time, is temporarily used as a monitor speaker for an electronic synthesizer. . Since the electronic synthesizer can produce subwoofers below 25Hz, if you do not pay attention at this time, and the power input to the power amplifier is still about 200W, the speaker may be damaged due to the excessive amplitude of the cone when it is below 60Hz .
In short, since different manufacturers have given various power calibrations for their speaker systems, and their respective test conditions are different, users must not just look at the value in the power column of the manual and use it blindly. Figure out the meaning of these data.
