All Pre 1970 Vintage speakers suck! Prove me wrong

Low efficiency, direct radiating speakers with voice coil-fitted drivers - as they're mostly represented today - have improved in a range of areas over the last ~50 years. ESL's fundamentally haven't. 

The pro segment of speakers have seen their improvements as well, not least for their intended applications and to accommodate in some cases a smaller size factor in the LF-region via different designs and much more powerful drivers, but as has been pointed to already a selection of vintage pro drivers have a dedicated following due to their sonic characteristics. Their lighter overall moving mass (incl. voice coils) - some of them with field coils and others with Alnico magnets - and lower power handling can lead to a "snappier" presentation as well as a fuller, more organic tone, not least as a distinctive feature at lower SPL's where they seem to come better to life. To me at least, while finding there's definite merit to their popularity, there's also sometimes a particularity to their sound that's not necessarily about "neutrality." Seeing also the prices of such units being often preposterously sized it becomes a niche market to a select, sometimes wealthy following of audiophiles that pursue of specific sonic imprinting. 

In any case I'd take most any of a range of older (or newer), larger pro horn speakers - typically aimed at cinema usage - over modern (or older) day low eff. hifi dittos with their vastly more realistically scaled, effortless and uninhibited presentation. Most domestically aimed horns/horn hybrid speakers fall short here as well being they're size constrained; while it may make them a better fit with the spouse and caters to interior decoration demands, a compressed size factor with this segment of speakers really robs them of their fuller potential. It's not about domestic or pro application here, but simply what serves the design and the physics involved - in a home environment as well. 

And that, physics, is what the pro segment of horn-based speakers got right from the beginning, many decades ago, so even while they were less extended in the frequency extremes they got the important basics right in a way that newer, smaller domestic designs in the same segment can only dream of achieving. And that's not about age, but rather - to reiterate the above - what complies with physics the best way possible. 

@inna ,

“Any vintage speakers that sound as good overall as, say, JM Labs Grand Utopia ?”

ohh hell no! IMHO of course lol. My dream speaker when they promote me to head cheese or I win the lottery. 

Looks like the lion is nothing more than a little pussy   cat.

Where is the lion hiding?

Some think, I heard, that Grand Utopia are one of three-five top speakers. They sound great even on youtube, that I can tell. Yeah, a bit expensive, not too big, though, quite manageable. VAC and Alnic electronics are popular choices with them.

There are probably one hundred speakers that qualify for the top five.  I certainly have heard but a small fraction of the speakers designed as statement products.  A friend who attends the Munich show and some shows in Japan throws out names of companies I have never even heard of their names.  I doubt that there would be anything close to a consensus of what companies should be near the top of the list if you polled those who have heard a lot of different speakers. 

Depending on the type of sound you like, the list would vary greatly and even if my taste differs dramatically from someone else, I would respect that list.  If, for example, someone put the Borresen flagship at the top of the list, I know that person favors open top end, speed, clarity and precise imaging (which are all good things), but, my own preference would be for a fuller sound and greater "weight" to the sound.  Would I put the Gobel flagship near the top (weighty, big sound)?  Maybe, but, it requires a lot of power which means the kind of amps I tend not to favor, so I would not know for sure unless I heard it in a familiar setting (which would never happen).  Would I put up for consideration a low-cost speaker with limitations on bass response, high volume capability, etc., but is SO musically satisfying (Charney Audio Companion)?  Yes, I might, and not just because it is reasonably price, compact , and practical (it is also high in efficiency); it just plain sounds good.  The same with the Songer Audio field coil speakers I've heard--lacking in deep bass, but very musical and reasonably practical.  The Rosso Fiorentino speakers?  I don't know, I heard and liked them, but, I need to hear them more.  It is pretty much impossible for me to make my own list of top fives, never mind someone compiling a more universal top five list.  My own personal list would not even have commercial systems on it--I've heard a number of custom builds that sound better than any commercial models I've heard.