The Shure V15 V with a Jico SAS/B stylus VS The Soundsmith Hyperion MR and Lyra Atlas SL

@bdp24 

A couple of obvious issues apart from those @mijostyn has pointed out.

1.  They have two drivers offset spatially by a considerable horizontal distance, which will give rise to comb interference with frequencies in the crossover region

2.  They have a crossover!

The result according to the video is that they are very hard to position.  Coincident source speakers tend to be very tolerant of room positions, and have much larger listening sweet areas ...

Dear @mijostyn  : I really like ELS and especially Sounlabs and Eminet Technologies even that the faster transients where MUSIC comes developed is through horns, yes as everything has trde-offs at both frequency extremes but in its specific frequency range ( depend of manufaturers and models. ) ESL just can't beats it and yes : as always seated at near field position..

Why I don't own horns yet? because its agresivity that many times surpass the liove MUSIC natural agresivity.

Acapella top of the line is a ery good blend of different speaker drivers and really good and expensive ones.

R.

The real wisdom is “ everything has tradeoffs “…. but knowledge and acknowledgment  of that is rarely demonstrated by those preaching a singular one true path answer….. 

imo the 63, of which i’ve sold ( new ) and rebuilt 4 ( several times over… the troubleshooting flow diagram is necessary but not, NOT sufficient, certainly has virtues but is hardly full range for various musical tastes….

@richardbrand: While it appears the tweeter of the DIPTYQUE could be a little closer to the midrange/bass driver next to it, the distance between the two is not too bad. The crossover point is 1600Hz, the wavelength of which is 21.45 centimeters. Most loudspeakers are worse than that in terms of the two drivers creating comb filtering issues.

The distance between the ribbon tweeter and p-m driver in the Eminent Technology LFT-8b/c is even greater, AND the crossover point is at the very high frequency of 10kHz, the wavelength of which is only 3.4 centimeters! I’m seriously considering having a new filter built with a more sensible crossover frequency, in the neighborhood of 1500-2000, assuming the tweeter will play that low without distortion. I would love to hear why on Earth Bruce Thigpen chose such a high x/o frequency in the LFT-8.

On the other hand, the p-m driver in the LFT-8b reproduces 180Hz up to 10kHz, with no crossover in that range. And it has a relatively high modulus of impedance of around 8 ohms, the panel itself 11 ohms (the woofer and panel each have their own pair of binding posts, making bi-amping simple enough). Far better than Maggies for use with tube amps.

@rauliruegas: In the video below Danny Richie examines the Klipsch Forte 1, and in that examination the reason most horn loudspeakers are extremely colored (imo) becomes obvious. Low coloration is a high priority for me.

https://youtu.be/QlVG0Qx5Ds8?si=PamEu5u61kkTlXSl

@mijostyn "you need to learn more about speaker design. The foot comes from the wavelength at the crossover point. ... What you are succumbing to is lay assumption and as we all know assumptions are the mother of all f-ups"   

So now I know that the "foot" comes from your assumption about the cross-over frequency - some mother of an assumption, especially with 3-way speakers which have two crossover frequencies! 

Your next statement is equally flawed "If two drivers are closer together than 1/2 the wavelength at the crossover frequency they function acoustically as one drive".

This proposition fails when reduced to absurdity.  Imagine the two drivers are omnidirectional and 1/2 wavelength apart..  Then along the line of the drivers, there is complete cancellation!  And on any other position, except equidistance, there is some cancellation.  Hardly functioning as one driver.

From memory you have made equally odd claims.  One is that only the sound from the closest point of your Sound Labs reaches your ear.  Well, if that were true, you could just keep an horizontal inch or so of the panel, and ditch the rest.  (See the reciprocity principle below).  The idea behind your assertion probably comes from that White Peper which describes the radiation pattern like the bristles from a bottle brush, entirely in the horizontal plane.

But that is not true either.  If it was, there would be no radiation to reflect from the ceiling and floor, and no need for the speaker to reach either!

The White Paper makes a big thing of an "acoustical principle that we refer to as microphone/speaker reciprocity".  I would not dignify it by calling it a principle, but it makes the case that speakers should be positioned as far apart as the (two!) microphones were, and the incoming (microphone) and outgoing (speaker) radiation patterns should match. The aim is that walking around the listening room should give the same experience as walking round the recording venue.

Why then, does this principle not also dictate that the speaker should be positioned at the same height as the recording microphone, and approximate it in vertical dimension?  I don't like so-called principles where you pick and choose what applies.

Walk round a concert hall (unpopular with the rest of the audience) and you will find sound coming from every direction.  Elsewhere I believe you have said the soundstage should be entirely between the speakers, and anything else is because wall reflections have not been eliminated.  Get real, decent systems can, and should, throw a soundstage extending far beyond the speakers, because that mimics the original venue.

"Quad was trying to improve dispersion. Stick with your KEFs"

Seems as if you are unfamiliar with the ESL-63 and later Quads?  Quad deliberately reduced the treble dispersion to "improve" it.