tweeter

A tweeter is a loudspeaker designed to produce high frequencies, typically from around 2,000 hertz to 20,000 hertz (20,000 Hz is generally considered to be the upper limit of the human ear). Some tweeters can reach up to 30 to 35 kHz. The name is derived from the high pitched sounds of some birds.
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n. tweeter, speaker that reproduces high frequencies

n. tweeter

woofer