The best speaker you ever heard?


In my opinion, the speaker is by far the most important part of the audio system. After all, it is the only part you hear. OK, the other stuff really matters a lot, but without a great speaker... No go.

I am a bit 'speaker-obsessed' I guess, and now I am wondering: What are the best speakers you have ever heard, and what made them the best?
njonker
And the Vandersteen Quatro's are just about dialed in at the factory.  Been on the phone with Johnny Rutan at Audio Connection all morning and setting up the install date.  I can not wait.  The more speakers I audition, the more I appreciate the Vandersteen line.  they just know what how to make a great speaker.  Thankful I gave them a second chance as the first dealer years ago just didn't set them up right and of course they didn't sound their best.  
Dali Epicon 6 driven by Simaudio and Nordost Cables. I was dumbfounded. Absolutely Holographic. 
not the best I've heard as that's the model two up in the line, but I have Vandersteen Quatro CT in Audi Havana Black paint coming home in the next week or two.  CAn't wait.
Vandersteen Seven Mk II with Aesthetix Calypso Eclipse pre, Aesthetix Romulus Signature CD player, Aesthetix Atlas Signature