One speaker louder


What could cause one speaker of a consecutive pair to sound brighter than the other? Both tweeters are working but one speaker sounds a little louder and sharper. A slight but noticeable difference.
neilmc
I swapped them, but no difference. You can tell they are the same speaker, but one has an airy quality, the other is more mellow.
You can tell they are the same speaker, but one has an airy quality, the other is more mellow

A dead or half dead tweeter perhaps?
Is there tone generating software that I can use to listen to high frequencies of both speakers?
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