I ran into this while testing drivers with LIMP:
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Published fs is 1475. So the yellow line is right on. The second tweeter (green) has a higher fs. I also tested a pair of Dayton ND16 tweeters. And they had a similar graph/issue. Just at about 1k higher. What does this mean? Anything?
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Also, any squiggles after the FS which can show motor issues