I’ve experimented for a long time with implementing a super tweeter into a single driver design and after about a year of back and forth, I decided that it never sounded completely correct. I used many values and brands of resistors, capacitors and even tried a L pad. I was working with the Fostex T90a. I came to the conclusion that to me I always felt I could hear a gap where the highs of my full range single driver cut off and where the T90a came in. Also the very highs of a super tweeter can sound bright. I had been using high quality resistors and I still experience this. I felt that the T90a never blended in as well as a good 2 way design. So if you ask me, if I had a single driver speaker and needed more energy in the top, I would be looking at high resolution cables, tubes or other tweaks that would help. Also, I strongly felt that instead of incorporating a super tweeter into my speakers, I should had went with a really good regular tweeter. Pretty sure it would had blended in better. BTW, I still have my single driver speakers and now I enjoy them very much. I use No super tweeters, just the single driver alone. I just used better cables and different tube amp. I also own these speakers, Rogers LS3/5a, Martin Logan Request, and about 10 tube amps, mostly 300b, and EL34 and 1 KT66 amp.