This thread will show the on and off axis response of all four of JBL's ring radiator tweeters. There seems to be some confusion over these so here is a mini background. All four tweeters can use the same diaphragms and have the same motor structure. There is an alnico and ferrite version. After having measured several of each tweeter in both motor types I am certain that there is a fair amount of unit to unit variation, but not due to magnet type.
The first model of this series was the 075 "Bullet Tweeter". There is also the Pro variant the 2402 and the ferrite version, the 2402H. This model has a the heaviest diaphragm of the three and is capable of operating over the widest frequency range. It also has the most focused dispersion pattern.
The next model offered was the 077 "Slot Tweeter" and it's Pro variant, the 2405. Later there was the ferrite 2405H. This model has the lightest diaphragm and offers the widest dispersion pattern and produces the highest frequencies.
The third model offered by JBL was the 076. There was also a Pro variant offered, the 2403 in alnico and the 2403H in ferrite. It was originally designed specifically for the L220. It uses a unique diaphragm. I believe that it has a moving mass that is between the 075 and 077.
The final model offered by JBL was the 2404H. It uses a mini butt cheek bi-radial horn. It uses the 2405 diaphragm, but is usable down to much lower frequencies than the 2405.
Here is an on axis plot comparing two brand new 2402Hs.
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