The best tweeter design

Well, just my opinion of course but...

The best tweeter/high end I’ve ever heard is still the MBL radialstrahler
omni design.

I still distinctly remember first encountering them at CES in 2000, wandering the grounds I suddenly heard for the first time what really sounded like live music coming from a room. I entered and the MBL 101Ds were playing some jazz. Aside from the obvious imaging and clarity, what struck me was the realism of the drum cymbals - they were actually full, big, round, dimensional and shimmered in the air like real drum cymbals. In contrast, every other speaker at that show, or that I’d ever heard before, sounded squeezed, like "tweeters."

Subsequently I heard various iterations of the 101s in better conditions and that aspect of their sound reproduction always impressed me. I finally got hold of a pair of MBL 121 monitors several years ago, which I keep around even as I go through other high end full range speakers. Every time I play the MBLs they just embarrass just about everything I’ve heard in terms of natural high frequencies - the most effortless, natural detail I’ve ever heard.  I know Jonathan Valin of AS touted the MBL tweeter as the best he'd heard for quite a long time (though I think he's described some new speakers as even better).

(I recently auditioned Raidho speakers, thinking of buying a pair, and their high end was indeed smooth, but overall they didn’t impress me as much as the MBLs).

steakster,

re amps and MBL 121s.

I'd had concerns that I would have to use more powerful amps than my Conrad Johnson Premier 12 tube amps (140W side).   But before I bought the MBL 121s I read that reviewer Peter Breuninger had used the tiny 14W classic Eico amp to briefly drive the much larger MBL 116 speakers, so that gave me some hope.  (I also own the Eico amp).
I'd also heard the bigger MBL 101s on tube amps before and they had never sounded better to me.

As it turned out I had nothing to worry about.  My Conrad Johnson tube amps drove the 121s beautifully - they have dense, punchy drive to the sound as well as finesse.    But what amazed me more was the little 14W Eico HF-81 amp on the MBLs!   The Eico's are simply magic in that they produce such a big rich midrange, with tons of "sparkle" and don't sound "slow."  But they do have a bit of an overripe bottom end on most speakers - the sound down there just gets bigger and deeper.

The Eico was an incredible combo with the 121s because it makes them sound lush and gorgeous, though not slow, and it gives the sense of deeper richer bass - the overall sensation is like it made the speaker "bigger" than it is. 

Ya never know until you try....