[img]
https://imgur.com/a/0QQhXaw[/img]
Here is a picture of the beautiful Michaura M66 with a modified Radio Shack Super Tweeter. When RS discontinued their super tweeters, I bought all I could lay my hands on. Swapped out the stock 2 cent capacitors for Solens or Auricaps I had lying around. Supposed to be flat to 50kHz. My dog agrees.
Anyway, the Michauras were made by, you-know-who, recognize the beautiful 6" black eye pea drivers and 0.75" Titanium tweeter?
Sound quality? pretty darn good, even driven by a modest Harman Kardon AVR445 using only 2 channels. I have twin Velodyne 10" subs in this system. When driven with the Antique Sound Labs MG Si 15dt 5 wpc SET integrated tube amp ... sound quality is superb!
So, what do the super tweeters do when their output is so far above our hearing threshold? IMO they definitely add "air" around the highs, improve imaging, and make for a more realistic presentation of music.