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

Or, as Sir Thomas Beecham said "The British don't like music, they just like the sound it makes"

@lewm There was a Branded Speaker back in the day using the HD-3P Tweeter. The Cabinet Volume and Matching Drivers even though Audax as well did not get the best from the set up.

A Build Your Own design become available as a Kit using a similar array of Audax Drivers

The more savvy builders of Speakers who adopted this design, were quick to produce much improved Xovers not constrained by a Commercial entities budget.

The next substantial changes for the Standard Kiit and more importantly the Commercial Design was the designs selected for the Casing/cabinets and External Xovers. Housing

Cabinets for the Build Your Own designs, were known to be produced from Board Material of a Thickness between 11/2 inch to 2 Inch. with all internal edges Chamferred.

Substantial Bracing with Chamferred Edges was adopted and independent chambers produced for all drivers.

These types of designs for a Cabinet were not known of in Commercial Speakers at a certain pricing, I suggest Speaker Cabinets were not produced to this Substance full stop.

My Speakers are With ext Xovers and a Cabinet using Board Material as sides up to a Thickness of 2 Inches, they are 5 Sided Cabinets with Chamferring Internally - Substantial Bracing and Chambers for the Drivers.

My Friends are Four Sided Cabinet produced from 11/2 Inch Board with ext’ Xovers in their own substantial housing.

The correction method adopted for the HD-3P Tweeter is a long term correction. It is now proven to have remained usable for a much longer extended period than the Audax Design.

As a Speaker it is another Bespoke Design, not typically encountered and not usually heard in use, which makes it one Speaker that is needed to be experienced to form an assessment.

I have recently been introduced to Troel Gravesend Design Speakers where Drivers and Xovers are approx’ £4K. The Cabinets and Speaker assembly were produced by Troel’s and exported to a UK Customer.

It is strongly suggested this design from Troel’s will be in the realm of £20K - £30K Commercial Speakers if a Speaker was to be searched out as a fair comparison. .

My gut feels, my friends or my own Speakers with carefully selected Upto date Electronics used on the Xover and PC Triple C Wire used as Internal / External Speaker Wire, will be a very very interesting Comparison, especially in the Upper Frequencies, where Troel’s is happy to allocate a £1000+ for Tweeters.

My own speakers were bought from an estate sale where the Widow told me her Husband’s System which was sold to a dealer was approx £100 K in total purchase value.

The Speakers weren’t Branded and not taken by the Dealer.

When picking up the Speakers, I gave the Seller very valuable advice on learning the Value of the Substantial Vinyl Album collection, where much of the collection was Classical.

She was now with new info to use and was to delegate the Grandchildren to getting an initial value using the Albums EAN No..

Classical Albums can acquire quite a sum as a purchase price, I hope some Gems were extracted for selling on.

@lewm With a very expensive Earthworks microphone. It is perfectly flat from 10 Hz to 30 kHz. They send each mic with it's own curve. If you had already modified your speakers the JC 1s would not have liked it at all. I blew mine up. Both died within 30 seconds of each other. Live and learn. Fortunately, I got them open box, but it was still the most expensive mistake I ever made. I was going to use them on subwoofers having already gotten the MA 2s. One of the MA2s got into trouble. After a driver tube shorted out two resisters and a voltage regulator burn out. While I was waiting for parts from Ralph I pressed the JC 1s back into service after I modified the backplates. Live and learn. Where your system rolls off is entirely dependent on the output impedance of your amps. My MA 2s have an output impedance of 1.75 ohms. 

@pindac I believe that is a super tweeter. Must of us would not be able to tell if it was present. It would also be a mistake to put it into a system based on dipole line source speakers as it's contribution would change with distance. I once experimented with  Magnepan Ribbon tweeters on my Acoustat 2+2s. Eventually I reverted to the plain loudspeaker. ESLs have a characteristic no other speaker can emulate. Having one driver than handles everything from 100 Hz to 20 kHz without any interference between the amp and the speaker is special. The image is spectacular. I do love estate sales. You can waltz into some incredible deals. 

@richardbrand I cannot imagine owning a speaker that could be so easily blown. In my hands it would not last 5 minutes. There is no excuse for a speaker to be so fragile. The materials exist today that can be used to make a totally bullet proof ESL panel. They existed back in 1978! Jim Strickland made a bullet proof panel back then. I can rap the diaphragms against the stators without any damage. The transformers are the elements that are potentially fragile particularly with amps that are clipping. I have blown amps and transformers but never the speaker itself. 

@rauliruegas Their Sharon Excalibur is quite the loudspeaker. I would love to hear them. The price is listed "on request" 

@richardbrand Do you realize that you have just noted that every great speaker designer is absurd, that the laws of acoustics are flawed. Don't listen to me. Get The Loudspeaker Handbook by John Eargle. It is written in terms most lay people can understand. Learn what you are talking about before you spew out ridiculous concepts. The British don't like music? I think you need to listen to V.W.'s The Lark Ascending. 

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.

Well, we know what music with no reflections sounds like: play it outdoors. It sounds 'dead.'

But too many reflections muddies things and getting it just right is a dark art that a few concert hall designers have achieved largely by luck.

Dear Mijo, You don’t need to teach me about the electronics, and no, I did not own the Parasound amplifiers any longer by the time I upgraded my 845PXs. In fact, my experience with the Parasound JC1s was entirely driving my M1s, which were completely stock in terms of the backplate components. With all respect to you and your quest for Nirvana, I perceive that the difference between you and several of us is that you want a perfectly flat in room response, regardless of the necessary interposition of the electronics (digital or other) necessary to achieve that. Whereas, I prefer the purest pathway with the least possible processing of the signal, come what may, with the exception that I do treat room reflections in my listening room with various wall panels and tube traps, etc, but that sort of thing is after the fact. You are operating on the signal in the digital domain before the fact. That (digitally correcting for droops and peaks in your listening room) has to be why you are stressing the MA2s, because there is no way they should be stressed purely by driving the Sound Lab speakers in the manner that you espouse. I tried equalization by signal processing once and hated it, but I admit the methods have come a long way since then. So I am curious to hear your system. Perhaps next time we go to northern Vermont I can stop by.

As to your response regarding how you measure in room response, "using a very expensive Earthworks microphone", etc, that is not a complete answer.  Where do you place the microphone? At what SPL do you map the response deviations from flat?