Learning a bit about electrodynamic speaker driver

 Speaker driver is what you see inside a loudspeaker enclosure as the active part which produces the sound according to the signals from the audio output of the amplifier. Tweeters cater to high frequency while woofers and subwoofers cater to lower frequency. Mid-range drivers reproduce the frequencies in between. A loudspeaker enclosure usually has all the three types inside. Below a woofer there will be a port known as bass reflex port, for enhancing the performance of the woofer. 

Outer part of the electrodynamic speaker driver is the chassis or frame, also known as the basket. Paper like cone fixed to it produces sound by its vibration. Voice coil inside a cylindrical permanent magnet, suspended on a 'spider' produces the linear movements of the cone for producing the sound according to the signal received from the amplifier. A dust cap prevents entry of dust, specifically ferromagnetic material, into the voice coil assembly inside the cylindrical magnet. Each driver unit has its characteristic impedance which has to be matched to the output impedance of the audio amplifier.



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