Thiel Owners

Good luck, bcarr38
In your previous post you wrote:

I have a pair of CS 2.3s with upgraded coax speaker which sound great but I am interested in upgrading

Was the upgrade the driver or crossover?

I am *really* happy with the CS2.4SE. It can't reproduce the left-most 2 or 3 keys on a piano but I can't hear any other weakness or shortcoming. I'm very curious to listen to a Vivid Giya or TAD Ref One or Vandy 7 again to discern how those designs are better (of course this will be confounded by changes in electronics and room). To be clear, I'm not imagining the CS2.4 is their equal but surely those speakers are near the horizontal asymptote on the performance/price graph.

have you thought about what might be the weakest link in your system? ie, consider upgrading you source or amp first? IME, these are just as important as the speaker.

On my 2.7's, i had been using the outrigger with the spikes that came with them. Replaced them with big brass feet from Mapleshade and that was a nice improvement.

Also, Avalon makes some cones (aluminum? stainless steel?) that I might try down the road. Probably the best result is obtained by using three per speaker but that seems a gravity risk!

@jafant  did you get a chance to inquire about driver availability?

good news for you guys

Kathy Gornik bought it back for pennies and will resume production of the CS2.4SE and CS3.7?
:)

In fact, he is working on becoming the owner/operator, solely, of Thiel Customer Service where our legacy products will continue to receive the care.

I figured that was the more realistic scenario, thanks for sharing jafant! Great news, indeed, Seems like a sketchy proposition for Mr. Gillium, though. Will he honor warranty service for products still under warranty? If yes, he can't possibly pay the bills, much less make a profit. Maybe there is enough post-warranty repair service to generate revenue?

Also, what is the remaining stock of drivers? Can he fabricate more? That would be cool if he is in possession of the machinery needed for that! From there, he is only a cabinet maker away from  . . .

Alternate timeline fantasy . . . What if Kathy Gornik had hired a tweaking engineer ca. 2010. Keep the drivers and cabinets pretty much the same but tweak the crossovers, wiring, and binding posts to the nth degree. Here's @lrsky  in another thread

Back in the day, I used to ask Jim Thiel why he didn't use better caps and air core inductors, resisters, etc, in his crossovers. He would coyly say, 'Because they measure as they do with the components I'm using.'

That was all well and good--but then the next day, I'd be talking to Bill Conrad of cj, and he'd be waxing poetically about the caps they were having made to their specs and how they spent hours deciding which cap goes where and so on. I was confused and frustrated with Jim, one of my icons.

Many years later, I realized that the 'pragmatic' business side of Jim was simply winning the battle for saving the world from bad audio, and keeping THIEL Audio in business. Every, we'll call it 'additional' penny(s) a manufacturer spends on internal parts, is a penny that doesn't come back as profits. So, if a $.58 piece of stuff works, why spend $4.35?

It wasn't until the twilight of Jim's life that he publically changed that position by making the CS2.4SE. As you may know, it offered upgraded parts in the crossovers. When interviewed, Jim said, 'Well, there are some things that can't be measured, but exist in audio.' I'm paraphrasing, but that's the intent of the comments.

I'll venture to guess that a tricked-out CS2.4 would retail for $10-15K but compete sonically with other designs up to $40K. A tricked-out CS3.7 might retail in low $20Ks but be considered as among the best speakers available.

But back to reality . . . best wishes to Rob Gillium!

@prof Do you think Jim Thiel was insincere when he told Jeff Fritz:

The improved resolution is not the kind of thing that shows up well in measurements; the magnitude of the difference between the CS2.4 and the CS2.4SE is more easily heard than discerned from graphs. The new capacitors allow more nuance, air, detail, and decay to be reproduced by the coaxial drive unit. This was especially evident to us when listening to recordings that contained realistic reverberation, as well as recordings where the instruments were not processed heavily.  

?

Though I would have been interested in a longer conversation with Jim, to draw him out on the subject and see how he may nuance things.

Well, I think it's telling that he called the Clarity Caps "boutique" capacitors. That sounds quite condescending to me. My supposition is that he was pretty firmly in the "objectivist camp" (measurements tell you everything you need to know) for most of his career and only reluctantly admitted, towards the end of his life, that measurements don't tell you everything.

There is no doubt that his designs measure superbly well (except as measured by Stereophile - JA's "quasi-anechoic" method limits the mic distance to a mere 50"). Soundstage's measurements of the CS2.4, for example, are among the best they have examined in terms of flat frequency response and low distortion. And I consider his drivers to be among the best ever made - near-pistonic behavior albeit handicapped by the slow roll-off of the first order filters. But that quote to Jeff Fritz, shortly before Thiel's passing, clearly indicates that he recognized that not all sonic improvements can be quantified by machines.

@jafant

There is an improvement between the CS 2.4 / CS 2.4SE, believe me, I spent many hours of listening to ensure that nothing was remissed.

So, you directly compared the two models? Neither of the webzine reviewers were able to make that comparison. I heard the original CS2.4 probably 12 years so I really don't have a reliable reference for how the SE version is better. All I know is that the SE version is incredible! Gotta give credit to my source and amp, but the Thiels are reproducing their signal superbly well.

FWIW, eBay lists a "crossover upgrade service" for Thiels -- I have not explored this though.

Yes, I saw this and exchanged a couple of e-mails with him. Me:

I am considering buying Thiel CS2.4s and am curious about your crossover upgrade. What does this entail? Is it similar or better than the CS2.4SE crossover with Clarity Cap capacitors? Do you need the speaker or would I install the new crossover myself? If the former, can you upgrade the wiring at the same time? Also, there is a pair of 2.4s on ebay right now but they lack the cable nut. Do you have any ideas for replacement of those (I have Cardas cables with the spade connection)?

Him:

You get clarity cap with vishey bypass in the tweeter section. Electrolytic capacitors will be replaced with new ones as they go bad after 20-30 years, also where possible electrolytics will be replaced with film caps or bypassed to improve performance. Inductors will be upgraded as needed with larger awg wire type and resistors in the tweeter section direct path will be replaced with film resistors or mundorf type.

Upgrade cost is $210 each.

The terminal posts on the back can be replaced. Not sure if I can find just the nuts.

Me:

So, $420 for the pair. Is this done in your shop or do I install the new boards myself?

If the terminal posts are replaced, can the new terminals be the Cardas clamps? Can it be re-configured for bi-wiring?

Him:

Yes this will be done at my lab and fully tested on the analyzer before shipping.

Yes you can go bi-wire, but fancy terminal posts can get quite expensive and using 4 of them will increase the price. If you have a specific terminal post you would like to use, let me know, send me the link.

Once we decide on all the detail we can figure out a final price.

Here is my website to understand more of what I do. I normally design as a consultant for some brand speakers, but work has been slow and am doing this ebay thing for the time being.

Nedlab.com

Seems promising to me. Who wants to go first? Might also be worth asking Rob Gillium if he offers upgrades for the crossovers. What we really need is a geek who took the time to experiment and listen with a bunch of parts combinations (it sounds like Jim Thiel did this when he selected the Clarity Caps). This is why, IMO, Wilson speakers perform as well as they do. The basic technology and drivers are, um, basic. But Dave Wilson, apparently, is a careful listener and finely tweaked his cabinets, crossovers and wiring accordingly. The final products is not without flaws but far better than otherwise.

I interpreted that as he does all the work in his shop - you have to ship the speaker to him. But I don’t know why you couldn’t instead remove the crossover yourself and send only that to him. Maybe it depends on how comfortable you are removing and re-installing the crossover. Also, I imagine he would want to be sure his mods work! In my case, I was thinking about buying speakers that needed to be shipped to me anyhow, so only 1 extra ride in the cargo truck.

If you’re serious, I suggest asking him directly including how many he’s done and ask his opinion of how the mods improve the SQ.

OTOH, if you comfortable removing and installing the crossover you're probably also comfortable upgrading the capacitors (and other parts) yourself. A good place to start might be the latest top-shelf Clarity Caps.

@marqmike Thanks for that story! Very encouraging. And, yes, you should upgrade the capacitors!

Thanks @tmsrdg! That is a timely phone call! And with fantastic news!

And way cool that he will coach you on the cap upgrades. Please let us know how that goes and how it improves the sonics.

It would be nice to think that someone could start making proper Thiel speakers again with all of Jim's concepts intact. Not holding my breath on that one.

If Rob Gillium has the machinery to fabricate the drivers it seems not far-fetched to at least start making CS2.4s again (I know they had problems with the more complex CS3.7 drivers and cabinets at the Lexington facility). Surely, at least a few of their old dealers would be willing to sell some, especially if the crossovers are updated with the latest parts.

Attn CS2.4 owners:
I’ve been thrilled with the performance of my "new" Thiels. One parameter lacking, however, was image density. My front wall is ~19’ wide altho’ confounded by a 4x4’ wall jutting in for the rear door exit in one corner. It is ~18’ on the sides. The ceiling is vaulted, 8’ on the front wall and ~12’ on the rear wall. There are two large openings on the rear wall, one just above my head; I sit within 2’ of the rear wall. I think the openings really "save my bacon" from unsatisfying sound with this room.

I did have the speakers about 10’ away from my ears to the tweeters and played with speaker spacing 7-8’. ~7’ sounds best but image density was not satisfying. I just spent most of the past hour experimenting with distance to the listening position, now have the speakers ~9’ from my ears and spaced at 7’ (7’ to the front wall!). Zero toe in. Image density is notably improved.

Anyhow, curious to read what other have for their placement. Thanks.

EDIT: Looks like my spacing is similar to what Shane Buettner used in his review: http://www.vandersteen.com/media/files/APJ%20Files/APJ13_Proof.pdf

Thanks for the reply, prof
6.5' seems close for Thiels. Seems like most listeners prefer at least 8', so I'm surprised to read about your set-up. Sounstage's measurements of the CS2,4, however, were taken at 2 m (~6.5') and the frequency response was outstanding at that distance (as opposed to Stereophile's inadequate measurement at a mere 50"). I hope your diffusor gives that result you want!

Thanks for joining this thread, Tom! My apologies for my role in incorrect speculation.

Thiel was always about finding the optimum point on the cost-performance slope so that real music lovers could afford our products.

I certainly appreciate this attitude. Thiel's top models were out of my budget, so I was glad to afford CS1.6 and, now, a used pair of CS2.4SE. Still, and I intend no offense, I've never had the impression that the CS3.7 and CS7.2 were a full-out attempt to deliver the ultimate in SQ. And, IMO, the area where these came up just a bit short was in the passive parts. As I've written elsewhere, it's also my opinion that your brother engineered some of the best drivers around. I suspect a tweaked CS3.7 or CS7,2 would sound pretty much as good as anything available.

I am stoked to read that Rob is planning upgrade service! Please make him aware of this thread. Thanks for taking the time to post.

break-in is something that many engineering-oriented observers dismiss as voodoo or make-believe or user acclimation. From the very beginning, we perceived its reality beyond question, but have never developed any definitive causal narrativeeyond question, but have never developed any definitive causal narrative

Yes, thanks for sharing this perspective, Tom. I completely agree. I’ve experienced break-in not just from speakers but from electronics and, even, cables. Just because we can’t explain or measure it doesn’t mean it doesn’t happen. 

boutique signal-path caps

This strikes me as denigrating language, BTW. At best, it implies stylish or luxurious, having nothing to do with SQ. Probably I'm nit-picking but wouldn't it be more sensible to call them "audiophile-grade" or "high performance" instead?

Yes, I’m just nit-picking.
Merriam-Webster:

1 a : a small shop dealing in fashionable clothing or accessories b : a small shop within a large department store
2 : a small company that offers highly specialized services or products

IMO, different word choice would have made it clear that Thiel thought the Clarity Caps improved SQ rather than imply a mere esoteric nod to neurotic audiophiles. Jim Thiel’s words in the UltraAudio interview were plenty clear regarding improved SQ but "boutique capacitor" as a bullet in a promotional brochure? Not so much. YMMV.

Regardless, I’m thoroughly enjoying my CS2.4SEs, boutique or not! I will contact Rob Gillum or Dave Garretson at some point and see about boutiquing them even more ;^)

I drove an equivalent distance to pick up my first pair of 3.5’s.

I recall reading on audioasylum that Charles Hansen thought the 3.5s were Thiel's best sounding speaker with the 3.7s a close second. But maybe I'm hallucinating as I can't find that post now.

To check for the leak, you can gently push in on the woofer and Passive diaphragms at the same time.

I'm very reluctant to try this. Supposedly, dimpled drivers have no measurable or audible effects but . . .

Maybe you can use something with a bigger surface area than fingers yet still softish?

Accuracy certainly is in the mix because these speakers sound about as real as a speaker can reasonably get. Because of that I think they walk a fine line and when people get an unfavorable impression of them i think they have not be set up well. I have never found them to be bright, lean, fat, tubby, warm, cold. They are about as spot on in the middle for me as a speaker can get.

I completely agree. None of the Thiels I've heard (CS7.2, 3.7, 2.4, 1.6) sounded overly bright or cool to my ears (altho' the CS1.6 could be strident at high SPLs with certain female vocalists, I think this is related to the distortion at 1 KHz seen in soundstage's measurements).

Shane Buettner's review of the CS2.4 opined that the midrange had a "slightly-on-the-cool-side-of-neutral sound" compared his reference Vandersteens. But I've also heard the Vandersteen 7 (which is a SOTA-level speaker, IMO), 3A Sig, Treo, Quattro, and I lived with the 2Ce Sig II for 10 years. I have no idea what he meant. To my ears, the Thiel CS2.4SE sounds very neutral, resolved, open, and transparent through the midband. In fact, it sounds superbly balanced at all frequencies. When I listen to performers that I've seen live, I have no trouble whatsoever imagining that they are in front of me.

My conclusion is that people complaining about poor SQ from Thiels have only heard them poorly set-up or with poor-performing amps and/or sources.

That "getting out of the way" quality of Thiels is awfully addictive.

 

Over the last 25 years, I’ve heard speakers from Wilson (W/P 7, W/P 8, Sasha, Maxx), TAD (Reference One and CR-1), Revel (M20, Studio, Salon Mk 2), Avalon (Eclipse, Ascent, Eidolon, Idea), Vandersteen (Seven, Treo, Quatro, 3A Sig, 2Ce Sig II), Aerial (5 or 7?), B&W (DM12, 804), Paradigm (100), Vaughn (Triode), Vivid (Giya G3), Vienna (Klimt), Thiel (CS1.6, 2.4, 3.7, 7.2) and probably many others I’m forgetting. My favorites are, in no particularly order, TAD Ref 1, Vandersteen 7, Avalon Ascent, and Vivid Giya (Thiel CS3.7 and 7.2 just miss the list). Now, these were all in different room with different electronics and over many years of sampling. But I have a good handle on what good sound is.

I’m here to tell you that my CS2.4SEs (driven by Ayre electronics) deliver nearly all of the neutrality, resolution and transparency – my sonic priorities - of the very best speakers I’ve heard. I would have to spend an order of magnitude more money to get significantly better performance in these areas and I suspect there are only a handful of designs at closer price points that can approach or equal the sound I am getting. I suspect the Thiel’s superb coherence is due to similar materials used for all diaphragms. And the resolution and transparency is probably due to the pistonic driver behavior over the intended range of each driver. Jim Thiel did a masterful job to ensure that driver break-up modes were well-suppressed despite the slow roll-off filters.

The only shortcomings I’ve noticed are the lack of low bass (which requires much larger drivers and cabinets and $$$), image density is not quite on par with the best I’ve heard (maybe my placement is not yet optimized?), and the highs are, maybe, not quite as airy and pristine as the very best. Should I be satisfied with getting “only” 90% of a Vivid Giya for $3000?

I think I have my “last speaker” (altho’ I may upgrade the crossovers at some point).

Note that the 2.4 SE only replaced two Solen mylar feed caps with Clarity SAs. Today there are much better caps available today from Clarity, Mundorf and other brands. My personal experience (via consulting for other brands) is that the upper end of the woofer circuit is sonically important, especially with Thiel's first order filters, and that budget is the only limitation to sonic improvement in a high-resolution system. I'll keep you informed as I finalize and test my conversion.

This is great information, Tom! Is there a particular cap you think sounds best for the 2.4? Please keep us (and Rob Gillum) informed of your findings. My understanding of the CS2.4SE is that the Clarity caps only involved the coax feed. Care to share any details regarding the woofer feed?

I suspect that hot-rodded Thiels of many models might make beetle's list.

Yes, I think I wrote this very thing earlier in this thread.

My apology for using the "B" word regarding caps. I meant esoteric high performance, not snobbery.

Yes, I was admittedly nit-picking. "Boutique" is too easily interpreted in different ways. I simply wish you and Jim had used more direct phrasing to indicate the sonic benefits of the more expensive passive parts.

Meanwhile, there is a pair of CS2.4s for sale, $1900, seller rates them 9/10. I kinda wish I had bought something like this and sent the crossovers to Rob Gillum for a full cap upgrade. This would probably result in SQ on par with anything new up to $20K or, even, $30K.

Thanks for the post, Tom
I'm very excited to try cap upgrades. Without further information, I'll probably try the latest Clarity caps that will fit in the 2.4 enclosure (which I have yet to open). Probably try some Cardas solder. Probably be weeks or months before I have time to do this,

@dgarretson

Owners of standard CS2.4 speakers may be interested to know that the only internal difference that makes a 2.4SE is the use of ClarityCap SA film capacitors. DIYers can make this upgrade or better by substituting the more recently introduced ESA range.

. I don't have a schematic, but during that time Thiel was purchasing 14uf and 28uf values. They may have been bypassing these with 1uf polystyrene caps. You should be able to confirm this by inspecting the crossover.

Since then we have surpassed SA by two generations-- ESA and now CSA. For that application I suggest CSA/250V or, space permitting, our top CMR/400V model.

You should inspect the board to be sure. The configuration is likely 14uf in parallel with 1uf(=15uf) and 28uf in parallel with 1uf(=29uf). If this is the case, then you could (1) replace the 14uf and 28uf values and leave the stock 1uf polystryrene caps in place, or (2) replace both the high values and the paralleled 1uf caps with 15uf and 29uf.

It is advisable to look carefully at the circuit before ordering anything.

Looking at Partsconnexion and Madisound, I don't see these values from Clarity (or Mundorf), especially as a close-up of the CS2.3SE crossover indicates 630 V. Are Thiel's values a special order?

@tomthiel Thanks for the clarification. This pic
http://www.hifishock.org/gallery/speakers/thiel/cs2-4se-2-thiel/
shows "Jim Thiel Signature" versions SA 28uF 630V and SA 14uF 630V. I cannot see a 1uF cap in parallel. The values on the woofer section are not evident.

I did not see these values online at Madiscound or Partsconnexion. Maybe I didn't look closely enough?

Also, is the crossover accessed thru the passive radiator or bottom panel?

@dgarretson Thanks for the reply. So, are the CS2.4 values available to the public? I will contact Rob Gillum for more info.

@tmsrdg Thanks for that info. Looking again on Madisound in the Clarity Cap MR 400V (is that enough voltage?), I can get to 28 uF with a 27 and 1 uF in parallel. For 14 uF I need the 12 uF and two 1 uF caps.

But given that I already have the Clarity Cap SA version in the coax, I should start with the woofer section.

Thanks, Mr. Thiel
I might pop one open this weekend and see what's involved as a DIY, see if I can find the values on the woofer section.

@marqmike Thanks for those posts. I think I’ll call Rob Gillum before I proceed. But I do want to look at the crossover to see if it’s a job I’m comfortable with. At a minimum, I’d like to at least take the crossover out at home to save on shipping costs and not risk cabinet damage during shipment.

I have two levels of upgrade specified for each of those first two products. 

Hi Tom
sounds like your plans keep evolving. Can’t wait for a report. Didn’t know the Cornell Dubiliers were back on your radar. Hope they don’t obsolete my RTX!

I'm less inclined to try the expensive Ayre

Just from the price points I wouldn’t think to match MXRs with CS2.4s, but I bet they would sound fantastic. Even more so with a Tom Thiel modded crossover. To repeat what I’ve written elsewhere in this thread, I suspect a modded 2.4 will compete sonically with other speakers up to $30K. 

He intends to develop upgrade kits for any Thiel products to meet demand. Other original Thiel operatives and myself intend to pitch in to help him succeed.

This is awesome! Thanks for posting this, Tom.

I am already spreading the word to Thiel owners.

Good idea. I just pasted Tom's post over at the asylum. We'd be smart to do what we can to support Rob's venture!

@sdecker Wow, that is *super* helpful information. Thanks! Would it be easier to remove the entire boards and replace the caps with the crossovers out of the cabinets? Your post got me thinking that a "real" modder would probably mount the crossovers in an external box (ala Avalon Ascent) to completely isolate it from cabinet vibrations. LOL - that's not me :)

(a 27uF direct replacement and a 10uF || 3uF = 13uF)

From Tom Thiel, Dave Garretson and the image I linked elsewhere in this thread, the CS2.4SE coax values are 28 and 14 uF. Are the 27 and 13 numbers for the original CS2.4 or did you decide to alter the values?

I’d post pictures if I could...

I'm hoping Rob Gillum will offer upgrade kits for DIYers as well as in-house upgrades. Ideally, this would include how-to pics or, even, video links on his website.

I researched the caps as needed here, and there are probably newer better caps since 2011, though for a price.
http://www.humblehomemadehifi.com/Cap.html

I gave a short look at this link. How does this guy have time and money to compare all of these, especially given the burn-in time? That top of the line Duelund looks interesting. Some of those sell for north of $800. Even if the OEM price is one-half of that, that would probably add $10,000 retail to put those in a pair of speakers!

The writer quite liked the Clarity CMR and some of the Mundorfs. A DIYer with money could get carried away . . .

Note, my PowerPoints are late-date manufacture from China.

Tom, did *all* the manufacturing move to China? I recall reading years ago that the round cap on the CS3.7 had to be made in China because of quality issues. I didn't realize until recently that the drivers were also sourced from China. And, now, you're saying that the PowerPoint drivers were made in China. What happened in Lexington? Is all of this on the new owners?

@tmsrdg I can't even find the name of the person who compared all of those. What is their experience? What is their system? What are their biases and preferences? IOW, how credible are they and how do we translate those words in ways that help us know which caps should be on our short list?

We get to "know" the hi-fi reviewers by reading their words and comparing that to what we experience when listening to the same product. Not much help for that in the case of these caps. One piece of credible info is that Jim Thiel and his team chose the Clarity SA for the CS2.4SE. Too bad we don't know what they compared it to. Also, Tom Thiel is steering us towards Clarity and Mundorf. One other brand that piques my interest is Cornell Dubilier but not sure if they make caps with the correct values for this purpose.

In the end, I might just go with what Rob Gillum recommends. I'm hoping he'll have a kit with all the parts, schematic, and DIY instructions.

It seems the site ate my detailed response.

Aww, bummer. Sorry to lose what must have been some great info. Re: Mundorf recs from Madisound, were those for Thiels?

I don't know if you can put pics in this thread but you can in the user systems section. Also, audioasylum allows pics.

Thanks for the added info, Tom. I will wait to see what Rob Gillum offers. I don't have time to pursue this now, anyhow. Just toying with the idea. If Mr. Gillum doesn't offer a DIY kit, I will probably start with the woofer feed given that my 2.4SEs already have Clarity Caps on the coax.

I have seen people "upgrade" Thiel hookup wire. I don't buy it. Thiel (lexington) hookup wire is 99.9999%, long crystal, teflon jacket, 3 twists per inch. I've never heard or measured better from any boutique / branded wire.

I trust your experience but I think I would at least try Cardas if I had the time and money.

Not anymore than I'm enamored by Thiel! Cardas cables sound terrific and many manufacturers with great sounding products use Cardas wire. YMMV.

My hope is to supply subtle information that may not be obvious to all. Crossover networks can be very easily scrambled via changes with unintended consequences.

I suspect I speak on behalf of this community in saying how grateful we are to have you here! I am very much interested in tweaking the last drop of performance out of my CS2.4s. But I have not the expertise, time, or money to try a multitude of mods. Your advice (and, hopefully, that of Rob Gillum) is *greatly* appreciated! I'm hoping you might write more about:

If I were hotrodding an upper end Thiel, I would consider a Teflon bypass in the tweeter feed.

Not planning any experiments . . . I hope to upgrade the crossovers exactly one time! Or piecemeal, given that I already have the Clarity SAs in the coax feed. ie, start with the woofer feed, maybe put newer Clarity (or Mundorf) in the coax feed as budget and nervosa dictate :)

From Tom's posts, the best bang-for-the-buck could be to "simply" put top-shelf bypass caps in. I might look at options from Cornell Dubilier in addition to Clarity and Mundorf.

I will continue to check this thread for more info from Tom Thiel and, hopefully, Rob Gillum. In the meantime, there is no doubt that the music in my living room is more clear, immediate, and involving than ever. And I want even more of that!

strat-a-gee article here:
https://www.strata-gee.com/king-thiel-dead-coherent-source-service/

Coherent Source website here: https://www.coherentsourceservice.com/

My "100 MBps" Comcast had a hard time downloading the pic of the CS3.7s!

Woo-hooo! Can't wait to learn more about "hot-rod kits". Crazy that he will honor warranties for legacy models. I hope he doesn't regret that decision.

IME there are very few integrated amps that are really ideal for most Thiel’s.

 
I'm getting superb results with my Ayre AX-5. On one hand, it is the only amp I've heard with the CS2.4SE. But on the other, I'm getting most of the SQ of the very best systems I've heard, eg, ARC Ref 250 driving Vandersteen Seven and Ayre R-series driving TAD Ref Ones. There are only a few systems I've heard that I would swap for mine straight across and all of them are considerably more $$$.

Stereophile's measurements suggest that the AX-5 prefers to work above 4 Ohms.

Hmm, must be all that Cardas wiring ;^)

Looks to me that it behaves very well into a 4 Ohm load. These would be good measurements for an amp *with* negative feedback hiding its problems, never mind a naked zero feedback design. At 2 Ohms, it does start to become "stressed" mostly below 200 Hz. I would probably hesitate to pair an AX-5 with, say, Thiel CS5 or Magnepan 20.

Lining the AX-5 measurements up with the impedance/phase traces for the CS2.4, it appears the most demanding frequencies for the Thiel are a bit higher up in the midrange. Nevertheless, one might wonder how these two might pair. As always in these matters, the proof is in the listening. My ears tell me they work together just fine, thanks. I detect no distortions or other unpleasantness at any frequency or SPL I've tried. YMMV.

If I were to audition and purchase based only on Stereophile's measurements I would not even give Thiels a second look, never mind own them! That upper midrange/lower treble suckout looks fatal! And look at all the hash in the waterfall plot! I'd probably own Revels and Halcros . . . and wonder why I wasn't enjoying my favorite music.

[OTOH, Soundstage's measurements of the CS2.4 taken from 28" further away are among the the very best in their database in terms of flat frequency response and low distortion.]

Welp, I at least we can agree that Thiels are great sounding speakers . . .