Triangle Antal Es and Thiel 2.4's

2.4's are not for everyone either. I bought a pair new after auditioning 2.3's in my home environment. I ran them with all the 'right stuff' (Pass X250, X2.5 pre, 306/200 CDP, Cardas Gold Cross, etc) & they were fully broken in. Problem was I couldn't listen to 80% of my CD collection. They rendered the music unlistenable. I must admit the 20% that was well recorded/produced was really good. by all means audition with music you listen to.

Thiel's are much harder to drive.

I own the Triangle Celius and am very pleased. i have heard the Thiel's several times and never liked them (however the rooms and set up were aweful)

The comments on the Triangles being bright is correct. I used an RTA to set up my system and can see the tip up on the graph. As such assuming one's hearing doesn't roll off (which is what I am counting on with older age) one can use a tube amp, avoid direct toe in or even put a 1 or 2 ohm resistor in series with the tweater until old age sets in. I run them on my 4 ohm taps which are a bit rolled off and don't point them directly at me. I love the speakers

From Stereophile review of Triangle Magellan Concerto:

"The impedance magnitude remains between 2 and 4 ohms over almost the entire audioband, and there is an amplifier-punishing combination of 3.7 ohms and a 44° capacitive phase angle at 78Hz. An amplifier capable of hefty current delivery is going to be a must with this loudspeaker.

In the time domain, the Magellan's step response indicates that all the drive-units are connected with the same positive acoustic polarity, the step of each blending smoothly into that of the next lower in frequency—but the ringing from the horn-loaded tweeter is very much in evidence.

Some things the Triangle Magellan Concerto does very well—the high sensitivity and dynamic range, the well-controlled treble dispersion, the optimally aligned bass tuning, the overall in-room response flatness. But its impedance will make significant demands for current on the partnering amplifier, and I don't like to see the resonant energy in the presence region and the top octave."

And from Stereophile review of the Thiel 2.4

"...despite Wes Phillips' conjecture that this speaker is not too hard to drive, its impedance plot (fig.1) indicates that the CS2.4 demands a lot of current from amplifiers. Not only does its impedance drop to 2.73 ohms at 600Hz, but it stays significantly below 4 ohms from 100Hz to 50kHz, and there is a difficult combination of 4.5 ohms magnitude and –45° electrical phase angle at 80Hz. Thiel CS2.4 owners should make sure they have a good 4 ohm–rated amplifier to drive this speaker.

The CS2.4's step response (fig.6) has almost a perfect right-triangle shape with just a small amount of leading-edge overshoot apparent, this correlating with the shelved-up top octaves seen in the frequency response.

Overall, the Thiel CS2.4 offers pretty good measured performance, its few idiosyncrasies resulting from the designer's use of a first-order crossover between the woofer and midrange unit."

Both require good amps to drive effectively. The accuracy in the time domain means that harmonic content is better preserved with the Thiel.

The Thiel will exceed at "timbre" over the Triangle.
If micro dynamics is your thing, then, the Thiel is your speaker.
I know this because I bought a pair. Happy Listening!