and frequency. Rated impedance audio is 400Hz, measured from the speaker input impedance. Usually it is a voice coil DC resistance of 1.2 to 1.5-fold. The general dynamic speaker common impedance 4, 8, 16, 32 and other.
3, the frequency in response to a speaker with the same voltage as the audio signals of different frequencies, the sound pressure generated will produce changes. General audio sound pressure, sound pressure generated in the low audio and audio smaller. When the decrease in sound