The best speaker you ever heard?

Probably the most striking speakers that I've heard were the new "Pure" series PureVox speakers from BMC. While I sat there, they just picked them off the display; placed them on the floor in front of their other big speakers; hooked them up; and played them. Shockingly good sound even then, but after a day or two they were awesome.

The ones I enjoy my music through every evening - Zu Druid V's with Dueland Cap upgrade.

I have to update my answer from the MBL 101 Extreme to the Rockport Altair. I heard the Altair at the Sound Environment in Omaha, Nebraska. They did things that I couldn't believe were possible. I have never heard their equal.

Mot

I've never heard speakers over 50k that sounded that much better than many under that price point. WIsh I had a dealer that had some of the esoteric speakers on display locally.

The best speakers I've ever heard are the Sonus Faber Aida. I have heard a couple pairs of speakers that are significantly more expensive that I didn't enjoy as much, although the Aida is certainly up there in price. The Aidas seemed to me to have a slight bit of warmth to them, but are still extremely detailed in a way that struck me as very natural and musical. For me, they have all the qualities I'd ever want in a pair of speakers if I lived in a world where I could afford them. I haven't heard anything I've liked better so far.