Are you talking about the true (?Vifa or Scan Speak I think) Revelator ring radiator? If so you are refering to a very highly regarded and well made tweeter which will respond differently to the electronics and enclosures used. They are very clean and can be extraordinarily musical. I have heard the real thing many times. Ring radiator simpy refers to to design which has been cloned and imitated of course more cheaply so be careful about the tweeter you are listening to before making any judgements.
BTW The first time that expression was used goes back to some 50s designs I know because I have compression tweeters with aluminum "ring radiator" housings from 1959.
BTW The first time that expression was used goes back to some 50s designs I know because I have compression tweeters with aluminum "ring radiator" housings from 1959.