[Definition of frequency range and frequency response]

The frequency range refers to the range between the minimum effective return frequency and the highest effective return frequency that can be replaced by the audio system; the frequency response refers to The phenomenon of increasing or attenuation, and changes in the frequency of phase. This changes (variable volume) associated by the sound pressure and phase and frequency are called frequency response, and the unit decibel (DB).

[Defense of the frequency of audio system]

The frequency characteristics of the audio system are commonly described by the vertical coordinate of the decibel scales to indicate the power and the frequency response curve of the frequency of the number of the numbers to indicate the frequency response of the number. When the sound power is 3DB lower than the normal power, this power point is called a high -frequency deadline and a low -frequency deadline for frequency response. The frequency between the high frequency deadline and the low frequency deadline is the frequency response of the device; the curve that changes with the frequency of sound pressure and phase hysteresis is called "amplitude frequency characteristics" and "frequency characteristics", which is collectively referred to as "frequency frequency" characteristic". This is an important indicator of the performance of the speaker. It has a direct relationship with the performance and price of the speaker. The more the scorer value, the more flat the speaker's frequency curve, the smaller the distortion, and the higher the performance. Such as: one speaker frequently sounds 60Hz to 18kHz +/ -3dB. These two concepts are sometimes not distinguished, and they are called frequent.

[How high the audio frequency is more appropriate? .

Theoretically, the frequency of 20-20000Hz is sufficient. The sound below 20Hz can not hear the other sensual organs of people who can be aware of it, that is, they can feel the so -called bass strength. Therefore, in order to perfectly play various instruments and language signals, the amplifier must achieve high -fidelity goals in order to achieve the goal of high -fidelity. Remains the harmonics of the tone. Therefore, the frequency band of the amplifier should be extended, and the lower limit should be extended below 20Hz. The upper limit should be increased to above 20000Hz. The representation method of the frequency response of signal sources (radio heads, recording seats, laser singers, etc.) is different. For example, the frequency response of the frequency regulatory stereo radio specified by the European Broadcasting Alliance is +/- 2DB when it is 40-15000Hz. Bring), the actual indicators that can be achieved are significantly higher than this value. The frequency response of the CD machine is 20000Hz, and the low -frequency end can be very low. There are only a few Hertz. This is one of the reasons for the good quality of the CD machine.