square waves from digital audio sources are very common, but low in amplitude and duration. They are usually less than 6 ms musically before flipping polarity. They also maintain their energy in their designated frequency
A clipped signal will max out amplitude and extend duration. When the signal clips, it also displaces energy into higher frequencies with just as much amplitude. Your woofer/midbass can handle that 200 watts for extended periods, but after the signal clip, you tweeters are now seeing the energy...
Clip = distortion = speaker staying at one extreme for two long = dc = bad
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