beryllium vs diamond

Hi guys, today's technology has brought us a new type of tweeter made of diamond or beryllium. Do you know what are the strengths and weaknesses of diamond vs beryllium? Which one is the more expensive? Has today's dome tweeter better resolving power than the venerable electrostat? Jim Thiel once said that dynamic designs will be getting better all the time and will probably surpass electrostatic designs.
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I’ve heard enough ESLs and big membrane speakers to know what they sound like, and they all basically sound the same. They present a massive wall of hyper-detailed sound with no sense of space
So full of it, you have no idea, you just described horns.

Over many years of audio, ESL’s have given me the best imaging in both side to side, outside the speakers, and in depth perception. No dynamic I have heard even Wilson Alexia MkII has ever equaled them.

But they wouldn't hold up too long being fed a steady diet of, Daft Punk, Tool, and DCD
As for your band/music taste, it explains now so much why you are the way you are.  
Manners, maketh the the man. Fine to disagree, less so to berate and belittle....
Hey Kosst_amojan the more a speaker disperses the worse it's image is going to be in any typical room. In open air they will image fine. I think your imagination may have the best of you. The membrane of an ESL represents a segment of the sound wave of a performance at a distance and it hearkens back to the stage in a way no other speaker can because it represents a segment of that sphere perfectly as there is no crossover. The ESL mimics the performance while the point source tries to mimic the performers resulting in a miniature sound stage and contracted depth as well as much more distortion and much poorer phase characteristics due to the crossovers and the nature of the drivers. ESLs can actually produce fabulous bass but you have to put them in an infinite baffle to make them work well which is totally and completely impractical for any remotely reasonable person so, the compromise is the subwoofer.
Because I am sure your hearing is just fine I know for an absolute fact that you have not heard an appropriately set up ESL infinite Line source system and they are not easy to find. Should you ever be in the Boston area I would be more than happy to demonstrate.
Now for those of you that want the ultimate point source speaker that will go loud enough to bust your eardrums you get four Accuton C168-6-490 midrange drivers and two C30-6-024 tweeters for a total price of $5000.00 Make a 2" thick plate 10" X 20" out of MDF and mount the midrange drivers on either side of the tweeter and as tight as you can to the tweeter. Make a simple 6 dB/Oct crossover at 3000 Hz. Cross to two subs at 125 Hz 24 dB/Oct. Lacquer plates to taste. I like Rasta. Don't forget to bull nose the edges. You might have to pad the MRs just a little. Hang the speakers from chains 1' in front of your wall right over the subs. The sensitivity will be about 93 dB 1 watt at 1 meter and the speaker should do 120 dB on just 100 watts! I would put acoustic foam behind the speakers. You would have to spend at least $30,000 on pre-assembled 
speakers to match these, maybe even more....much more. Life in the fast lane. 
I agree that silk domes can be awful as well with crappy implementations. I like a slightly forward sound but have been hearing a lot of speakers that take it way too far lately.

verdant audio, I appreciate people like you providing us with the knowledge gained through your study and experience. It is certainly more welcome than the incorrect info and bickering often found on forums.

Detailed and forward sound seems to be one current trend in high-end speakers. Apparently you are working on a different path and that’s good. I don’t like bright, forward speakers myself.

Another big problem for me on forums is that people believe that not only should everyone like what they own, but that their gear is the best available and you are an idiot if you don’t agree.

I’m not accusing you of that. You have extensively listened to a lot of Be tweeters and don’t like them. That’s good to know, but my aging ears are probably not as sensitive to their problems as yours.

Maybe you could give them a try in relaxed listening mode rather than in critical listening mode sometime and let us know the result. I know that conducting comparisons is one way for me to be sure I won’t like a speaker, but that's just me.

Good luck with your speakers!