Key performance indicators speakers include: sensitivity, frequency response, rated power, rated impedance, directivity and distortion parameters.
1, rated power
Speaker power has nominal power and maximum power of the points. Said nominal power rated power, power without distortion. It refers to the speaker rated content without distortion allowable range of the maximum input power of the speaker's trademark, technical instructions on the label is the power value of the power. Maximum power is the speaker in a moment can withstand peak power. To ensure the reliability of the speakers work, requiring maximum power of the speaker 2 to 3 times the nominal power.
2, rated impedance
Speaker impedance general and frequency. Rated impedance means when the audio is 400Hz, the input from the speaker impedance measured. It is generally 1.2 to 1.5 times the voice coil DC resistance. Usually dynamic speaker common impedance 4Ω, 8Ω, 16Ω, 32Ω and so on.
3, the frequency response
A speaker is coupled to the same voltage and the audio signals of different frequencies, which produces a sound pressure will change. Sound generated when the general audio compression large, and the sound generated when the bass and high audio pressure is small. When the sound pressure drop is high, the bass in the audio frequency range when a certain value, called the speaker's frequency response characteristics.
Ideal frequency characteristics of the speaker should be 20 ~ 20KHz, so you can put all the audio evenly reproduced, but it is not. Each speaker can better reproduce only a portion of the audio.
4, distortion
Not the original speaker's voice vividly reproduced the phenomenon called distortion. Distortion in two ways: frequency distortion and nonlinear distortion. Frequency distortion is due to certain frequencies of playback signal stronger, while for others the playback frequency weak signal caused by distortion destroyed the original proportions of high and low sound, changing the acoustic sound. The nonlinear distortion is due to the fluctuation of the vibration speaker vibration system and fully consistent enough signals caused by adding a new frequency components in the acoustic output.
5, the directional characteristics
Used to characterize the speaker in the direction of the space radiation sound pressure distribution, the higher the frequency the more narrow directivity, the greater the stronger directional cone.