What's the best mid-range driver available?

Yes i found access to the ATC's. Since we're on the subject of "best" midrange, it's good you brought up the Raven 3. This ribbon is one very interesting speaker. If i chose to go single source driver this would be the one. The R-3 does go down to an amazing 500,i had thought it was 1K. Zalatroyn has a kit with the R-3. New York Noise Maker. You can see the xover schematic and a picture. The NYCN has dual Focal 10 inch Kevlar woofers in each cabinet. Quite a load for a tube amp i would guess. They xover at 500, which seems low to me. I would feel 1K would be a better xover point, so as not to stress the R-3. Though the unit does looks like it's built like a tank. The R-3 could offer a seemless image that the ATC + tweeter may not. If i used the R-3's i would go with the new Seas W26. W26 + R-3! What a speaker!!...for under 5K!

One drawback of the R-3 (in my opinion anyway) is the limited vertical listening window. When you stand up, you lose the highs. Now I probably place a higher premium on good sound while standing up (and dancing) than most people do. But if I were using the R-3, I'd probably want to use an R-1 or (egads!) Pioneer leaf tweet for the top end.

No doubt about it though - sit down and the R-3 is stunning.

If you decide to call Orca with questions about the R-3, ask for Allen Hulsebus. Allen is one of the finest loudspeaker engineers in the business, though his work never ends up with his name on the box.

New kid on the block...Zellaton, don't know much about the driver right now i'm researching. E-speakers has them on order. I just got a note on Madisound from a DIYer who has all the midranges on his table. He votes on the Zell's...???As soon as i know something i'll post. The Etons got votes as well.