Has anyone heard in depth the TAD-1 loudspeaker .

No, I heard the TAD-1 speaker. Dr. Edgar and I heard the TAD-1 at CEDIA (I just happened to be there when he was there). I again heard it at CES. At CEDIA I had a chance to talk to Dr. Edgar after the demonstration. We both agreed that the speaker had incredibly lifelike dynamics. When I commented that it sounded a bit too metallic and hard, he said that he has tried all sorts of things to tame that quality in the beryllium drivers that TAD does sell (not the same drivers as in the TAD-1) but could not do so. He said that this was a bit frustrating because, aside from this quality, he really likes the beryllium drivers they do sell.

I hope I did not sound too negative about the speaker, because I think they have great promise. I hope to hear them in a different setup than the ones at CEDIA and CES.

I have only heard the TAD speaker at CEDIA and CES, not under better circumstances. They are extremely dynamic sounding and have a very extended frequency range. But, they sounded quite hard and metallic. Was this the nature of the speaker or the electronics (primarily Bel Canto)? I don't know.

I just happened to be auditioning the speaker with Dr. Edgar (Edgarhorn) and he thought this was the inherent characteristic of the beryllium TAD drivers. He said that he loves the dynamics and clarity of TAD metal drivers, but could never tame the metallic signature when used in his designs.

In short, this is a speaker one must hear when shopping in this price range. It does something other pricey speakers don't do, specifically, bring the music to life. But, the excitement may turn to annoyance in the long run. If the hard, edgy and raw (sounds a bit unrefined) quality cannot be tamed, I personally would pass on them. On the other hand, I also don't like the lifeless, dull quality of some other premium speakers like the Avalon Eidolon, Kharmas and Grand Utopias.

Another quite dynamic speaker worth giving a listen to in this price range is the Overkill speaker using the Manger driver. It has a very narrow listening window (poor dispersion of highs) and some problems with integration with the bass driver, but it does give music that jump factor I favor. My own speakers, SAP J2001 (twin) are, unfortunately, recently discontinued (for something that retails in the US at $22k and looks like it was assembled in a garage, it seems hard to believe the manufacturer's claim that it is too expensive to build).