Thiel Owners

Brett - what you say has merit. Deciphering phase / polarity behavior has a lot to do with the ear-brain's reference, and having the deep bass delayed does affect the overall sonic fingerprint. But keep in mind that the vast majority of speakers introduce such phase distortion at every crossover point. That global, full-range scrambling may obscure the phase picture enough for the ear-brain to stop caring, drawing attention to Thiel's polarity sensitivity. I concur with your observation.

JA - I think that Jim's passives were spot-on, textbook best implementation. And the frequencies are low enough to be out of the critical midrange area. It is solid bass. The only real compromise is the inherent phase lag of the ported /  passive deep bass driver. 

Brett: "They would be insanely amazing if they had actual cones driven for the low bass." That debate was real in our company. Jim began the subwoofer development project with hopes of incorporating active bass into the model 3 (4) and 5. Class D was in its infancy, and that project took further years to bring to fruition, so the model 3.6 was developed with a passive/ported bass and further models followed suit. I personally lobbied for keeping sealed bass in the model 3 with an implementation of bi-amp possibility for the woofer with a higher output woofer for the model 3 and develop a model 4 with the additional low-woofer for a sealed 4-way to fill in to the sealed 5-way model CS5. The lower-priced models 1 and 2 could use the ported bass.
Those decisions were made by Jim as CEO and Kathy as Marketing Director. As we all know most speakers on up into $6-figures employ ported bass as a cost-effective solution for deeper bass with higher output capability. But I, and it seems you, and possibly many others think that the otherwise seamless coherence of Thiels above the low bass spotlights that timing inconsistency of the ported bass alignment.

i just purchased Thiel CS6's and yes i hear a huge difference when i flip the phase. I use my Sonic Frontiers Line 2 preamp to do this. 

I would guess its because the passive radiator is inherently our of phase with the rest of the signal. when the woofer cone moves out to create a mid-bass hit the passive radiator must move inwards. and i think the speakers were designed so that the natural physical crossover between the woofer and the passive radiator is at a common junky room resonance node (so he could hide the absence of some bass).

When I flip the phase I like them better because the low bass hits first, but you will then encounter one resonant room node in your upper bass. And it makes the stereo image recess instead of come forward.

They would be insanely amazing if they had actual cones driven for the low bass. 

JA - if and as a small company might be created to keep Classic Thiel speakers updated, all models are in the mix.

Hi Tom,

Please remember the American moto: "Close but no cigar".  We at the end will want "cigar" :-)

Dsper - not to worry, eventually we'll make them sing.

Thanks tomtheil,

I have CS5's. Shucks!

Last weekend I had the chance to visit Glenn Poor's Audio and Video in Champaign IL, had some questions about my BAT VK-55, and luckily Geoff Poor was in the house.  I told him about my set-up, he said he sold Thiel back in the day, loved their speakers, was complimentary of my amp/speaker pairing (salesman alert!), and then, unprompted, he offered up that "most people don't remember, but Tom Thiel was a true craftsmen, the fit-n-finish of his cabinets were always superb, and what a lot of people don't realize is the enclosure and cabinet design and manufacture was a good part of what made the speakers sound so good."

Then he had me listen to some new Quads and I was blown away, even with the flash-drops.

Enjoy your weekend listening to music!

JA - if and as a small company might be created to keep Classic Thiel speakers updated, all models are in the mix. What emerges as upgrade solutions will apply to all models because the design goals and methodologies of all models share their DNA so closely. My beginning point is early models for many reasons, but eventually I hope we can also shed light on newer models.

@sdecker 

My analog section is decent: Kenwood 500 (direct drive) mounted with BenzMicro ACE, tonearm wiring replaced with Cardas feeding an Ayre P-5 . . . But I almost never use it. Until this week, I hadn’t used it at all since probably last winter. 24-bit files sound superb through my DAC, all the textures of vinyl combined with the dead silent digital background. Best of both worlds. 
I am planning to try Tom Thiel’s solution but probably not until after my “new” DAC settles in. Thanks for your observations about the baffle morphology on the 2.3 v 2.4. Very interesting! I’m motivated to experiment.

I've never been certain how the 2.4 steel frame grille plate affects the diffraction 'problem' as it tightly surrounds the coax with 3 cuts at about 20 degrees, 0 (vertical), and 30 deg.  But the steel still presents as an edge, a discontinuity, for the coax wavefront.  It is just closer to the coax than the baffle edge when the grilles are off.  If you removed the grille cloth off the steel frame, it would more-clearly visibly *appear* to be problematic wrt 90 degree discontinuities closely around the coax.

I'm happy to entertain the soundstaging differences are from something unrelated to the baffle differences, which appear to be such an obvious contributor.  I've had my 2.3 coaxes in my 2.4s for extended periods waiting for replacement 2.4 coaxes, but beyond an interesting change of frequency balance, couldn't discern any soundstaging differences...

Absolute phase (polarity) more noticeable through Thiel speakers. Thoughts??

My VTL preamp has a “phase” switch on the remote. I never heard much of a difference with previous speakers, but on my 3.7s the difference can be quite striking...

Fellow Thiel-ers.  RE: 3.5's and amplifiers.  Just a post for whatever it means to you.  I've replaced a series of SS amps with a pristine used VTL ST-85 (paired with a Counterpoint SA-1000 preamp and a Counterpoint SA-2 headamp.  Magic!

This amp is much better than the Audio Research D90b I used to use with these speakers (before the SS's.)  The 85 is optimized for 5 ohms, exactly what the 3.5 needs (impedance 4 ohms to 6 ohms over most of its range.)  The amp is rated and delivers 85wpc at that impedance, and has an absolutely flat power response down to 20hz according to the QC chart that came with mine.  Bass of course is not equal to the SS's, being less controlling and tight.  But oh my, the naturalness and 3D of these pieces even with less than optimum speaker environment is superb.  And the power is sufficient to have normal listening levels in the next room when I am working at my computer.

BTW, the VTL also sounds superb with my 2 2's which are even more transparent, but I was expecting that.  It is with the supposedly power hungry and "veiled" 3.5's that the surprise happened.   As I sa id, make of it what you will.

Hi Tom,

The other part of the equation with respect to the CS2.3 vs. CS2.4 is evaluating with our listening test.  Personally, I don't know if the difference as reported is due to the baffle "edge".  The difference could may as well be the xovers, bass driver and so on ...

sdecker - let's not conclude that the baffle pocket is a sonic problem. In fact, the 20 gauge steel grille plate with its fabric fills that pocket to be flush with the edge curves. The inner edges are not parallel or concentric with the driver, and therefore probably produce little, if any reflections / diffraction.

My work is not to fix anything that was broken in the original design, but to look for ways to add more subtle solutions. One such solution is in the SoftLaunch of the baffle supported wave. I have not dealt with how to incorporate the grille into that scheme, but rather how to optimize the driver / baffle / surface interface. On the earlier speakers the curves are continuous with the front flat baffle and the grille frame is outboard. That's my present sandbox. On the 1.6, I had imagined a solution like the 2.3, which I have not yet seen, but such a solution would also work for the 5, 6 and 7. It's all a puzzle.

Oops, that reply should have been to sdecker.

Andy - my experiments show that a felt edge at the driver surround is not good. It causes its own reflection / diffraction effect. Good results have come from beveling the felt edge and by covering everything up to the surround with Ultrasuede for an uninterrupted surface. Other designers have cut star or odd shapes for the drivers to peek through. But I don't like that either.  I may have spoken too soon. I am in the middle of this stew and perhaps you might sit tight and learn from my progress as things get clearer.

@andy2
That's exactly my concern, problematic diffraction effects for the sake of "aesthetic appeal" fly in the face of all I came to know of Jim Thiel's design ethic.  And yes, he was alive and kicking throughout the CS2.4 project.
@beetlemania  
If your analog front-end is up to par with what I read earlier of your amplification, it would seem vinyl would be at least the equally-good source for critical listening!

I guess I'll be paying a visit to a tailor for the first time in decades (!) to try some of these materials.  Perhaps I could just put the felt around the coax's metal perimeter, up to the surround, as there isn't enough space to mill out the grille metal to the left and right of the coax baffle area.  That would seem to defeat the idea though, as I'd be attenuating all the coax output that isn't straight-ahead, vs allowing it to freely disperse unobstructed.  Which takes me back to the compromised 2.4 baffle in its entirety of construction :-|

Beetle - FWIW, my experiments have led to a 2-layer system as having sonic synergy. Not ready for prime-time, but anyone is welcome to play.1/8" F11 (or F15N) felt plus top layer of Ultrasuede LT (lightest grade 0.6mm thick). And the clencher is covering the driver plates or bezel rings with Ultrasuede LX (stretchy), right up to the surrounds. Together these surfaces make some magic, both heard, as inner harmonic detail, and measured as lower group delay, harmonic distortion and waterfall decay. Problem is that samples of these materials are hard to get and alternatives (fake Ultrasuede or other felts) do little good. Still working.

@twoch I've done tie-dye once but fail to see how that is relevant to this thread.

@tomthiel @sdecker  OK, you now have me very curious to try a baffle treatment. But my DAC is away getting an upgrade (I'm currently rediscovering my LPs), so I'll have to let that settle in before I can do a fair test of changes to the baffle.

I agree that the CS2.3 baffle is cleaner vs. the CS2.4 in term of "diffraction".  I never noticed the difference before.  Maybe the motivation for the CS2.4 baffle was about the "aesthetic" appeal.  

Thiel Owners ,  that's a dyeing breed 

sdecker - thanks for the photos. On my 1.6s I put a strip of aluminum at the bottom of the pocket to support the weight of the grille. Of the various felts I have tried, the best is F11 pressed wool from Sutherland. F15N (needle punched) is nearly as good and costs half as much. I have tried 1/8" and 3/8" and don't hear or measure much of any difference. Probably land around 3/16" depending on physical parameters.

@tomthiel     
Sure wish I could post images directly.  Doing a google image search on the speakers in question will produce a few with the correct angle to view the issue at hand, below.

The 1.6 (and 1.7) are similar to the 2.4 about my concern of the recessed baffle.  The 1.5 is a very different mounting strategy from the 2.3.  The 2.7 baffle is again different from both the 2.3 and 2.4.

I will play with your felt solution with my 2.4, but in their case, this will disallow use of the grilles w/o some klugy modifications: most of the grille weight is supported by a pin above the coax, requiring the grilles remain flush against the baffle; the magnets help support the grille perimeter.  In my home, the grilles must remain on.

Here are quick and dirty links to reasonably good views of the 2.3 and 2.4 baffles:

https://www.alibaba.com/product-detail/Thiel-CS-2-3-Hi-End_11195163.html

http://www.hifi4sale.net/t38695-thiel-cs-2-4-used

dsper - noise floor reduction is an element of greater dynamic range, but the ear-brain is very good at inferring musical signal that "should be" buried in the noise floor. Yes, quieter is better, but it isn't everything. I suggest classic troubleshooting - find some other components to swap and determine where your noise is coming from. Could be tube noise.Speaker noises can include a throaty hissing, usually under load, if capacitors are failing, but I would rule out the amps first.
No need to unscrew anything. Take off the grille and inspect the bottom and third (sub) woofers for rubber mats (CS5) or center weights (CS5i).

tomthiel,

"...hiss is coming from the amp chain, not the speaker.The CS5 has rubber pads on the upper and floor woofer and the 5i has center weights..."

Tom, please bear with a couple of basic questions:

1. Reducing hiss then, is around acquiring quieter components in the chain. This would then also reduce the noise floor and allow more detail to be heard?
2. If I want to check if I have CS5's or CS5i's, I simply unscrew one of the woofers and look at it?

Thanks for your advice!

Dsper

Happy Friday! All

With all these variables related to parts of a passive xo, any experience how a passive xo compares to a digital active xo? Maybe I should hook up my passive xo again.

Beetle - I concur with your results and consider the passive parts to be important and know the work Thiel put into finding best bang for buck, always knowing that more bang could be bought. The shunts are in my experience more important than generally thought. In an AC resonance circuit all parts are in play. I am approaching the physical stuff first for practical reasons; I can compare multiple speakers with various treatments to gain experience with less investment.
Dsper - the hiss is coming from the amp chain, not the speaker.The CS5 has rubber pads on the upper and floor woofer and the 5i has center weights.

the 630V caps and far-more-expensive Mundorfs et al were simply too big for the space on the XO board

The higher voltage versions, with thicker film, are reported to sound better. I didn't compare different voltages on the coax feeds but did directly compare 160 and 250V versions on the woofer shunts. Some say that shunt cap quality makes little, if any, difference in SQ but, to my ears, the higher voltage version sounded a bit more relaxed and with more bass heft and impact. A subtle difference but one I am willing to pay for.

In my case, the larger caps were not an issue because I started with completely new boards/layout. So, no need to fit a new cap into an existing space.

Thanks for your post, Tom.
Interesting that Rob found the ESAs to sound worse. My experience was that nearly every change improved the sonics. Perhaps because I had a good coach ;^)

I am considering those electronic upgrades as end of project decisions. My focus is on re-bracing and re-baffling which is progressing well.

As you know, I'm a big fan of upgrading the passive parts. And I think a lot of the improvement I hear can be had for less money. That said, I'm looking forward to trying your baffle treatment.

Hi All,

I have a couple of CS5 questions for the Thiel experts. 

1. how does one determine if they have CS5's or CS5i's? I read somewhere, I think on this thread, that there is no marking on the outside of the speakers to tell? My serial numbers are 1225 and 1226.

2. When I turn my system on with the preamp allowing no volume, I can hear different sounding "hisses" from each of the three small speakers on the top. This is audible only with my ear within six inches of each speaker. Is this normal? Or is it a sign that something is wearing in the crossover, etc. Or could it be coming from another piece of equipment like a tube preamp?

Thanks for listening,

Dsper, 

sdecker - I don't have those models to inform any opinions. But I am messing with the CS1.5 and 1.6, which exhibit similar baffle differences. The 1.5's grille board mates with the baffle to form a flush surface with 1" radiused round-overs. The 1.6 has much larger round-overs outside of a shallow (1/8" - 3mm) pocket which holds the metal grille panel with cloth over it. I believe the 2.4 and 2.7 are like the 1.6. Within all those variables, I have isolated a sonic and measured glitch caused by that grille 1.6 pocket, either the edge of the metal panel or the edges of the pocket with the grille off. Filling that pocket with 1/8" F11 wool felt eliminates the glitch and the speaker sounds larger, the image lifts and comes out of the box. With the felt in place, the treble balance sounds right without the attenuation of the fabric. The grille magnets work through the felt for protection when needed.

This discussion segues into the grille cloth thing. A manufacturer must decide how to present its products to market, and Thiel chose wood cabinets with fabric grilles, for better and worse. Reticulated foam (model 01, and a Wilson special order) is more transparent, but not very cool-looking imho. Our fabrics got more and more sheer as they became available, but it is still there as Andy mentioned. I believe most audiophiles would prefer no fabric. In fact Thiel offered grille frames with no fabric and extra finishing to match the baffle. Nice, direct sound, but with more high-end sizzle. We could have, but chose not to modify the XO to knock down the treble. A hot-rod shop such as Thiel Renaissance could offer such mods to make the purist happier. I am presently experimenting with solutions that optimize sound quality and aren't physically objectionable.

   It turns out I *did* post to this forum about my 2011 XO upgrades on 2/2/18 (pg 49), with beetlemania and others acknowledging my relatively early surgery. 
   My 2.4s are fairly early production (SN 611,612) so I can confirm the high(er) quality original XO parts (including the inductors), point-to-point boards (literally), and wiring. 
   Due to nobody posting about 2.4 XO specifics in 2011, I had to wing it with only the schematic and XOs in front of me and Thiel telling me their use of Clarity Cap SA.  So I wasn't about to second-guess their use of film 1uF bypasses.  I had evidence the ESA I ended up using was a better-sounding cap than the SA, the CSA wasn't available yet, and the 630V caps and far-more-expensive Mundorfs et al were simply too big for the space on the XO board, so I used 250V versions.
   I don't doubt the XO can be improved well beyond what I've done, but as Tom Thiel points out, there are risks and pitfalls to just throwing the best and fewest parts at such a carefully-modeled 2-way XO.  I look forward to reading what Rob Gillum and team can accomplish with more resources than were available to me at the time!

   And I'm still waiting for informed comments about the compromises of the 2.4 baffle versus the smoothly rounded 2.3.  The 2.7 did away with the baffle discontinuities and should sound that much better due to both the baffle and certainly the 3.7 coax.

I don't have full vs 1uF bypass comparisons, but I do have some relevant history. When Thiel developed the bypass configuration, caps were relatively primitive, and smaller value, higher spec bypass caps made a significant improvement. We developed that 1uF tin foil x styrene cap as state of the art and used it for nearly every station. Note that the CS3 had teflon nF double bypasses and the CS2 and 3.5 had styrene ultra bypasses. As caps got better, the ultra bypasses became effectively obsolete. Note that multiple caps help and hurt. They hurt timing precision, since their discharge rate is faster than the larger value, and each station must be tuned. Effectively cost-prohibitive in our particular niche. 

When Jim was developing the SE, Gary and Rob report that they listened to and measured many, many configurations of bypasses and brands of caps including darling  audiophile cost-no-object ones. They chose the then-best Clarity SA for its rightness, both measured and heard. The single (non-bypassed) value was chosen as sonically superior to the bypassed version. Note also that the CSA, with its copper spluttering, is said to be a league ahead of the ESA, which was a relatively small advance over the SA.

Beware that the incision of these higher grade components comes with its own set of potential perils. In Lexington last week I saw Rob's 7.2 XOs in which he had replaced all series feeds with ESAs to compare with stock. He (and his cohorts) preferred the stock parts. The point is that the whole thing is a pot of soup, and "improving" something may require other compensations. When converting Beetle's 2.4s, I was relieved that every upgrade resulted in upgraded performance. As he mentioned, his SE's were late Chinese manufacture with room for improvement by reverting to old methods, from which we also upgraded layouts and coils. All his parts were very carefully selected, and synergy ruled. My own path is with Mills resistors and Clarity caps on old-style point to point boards with new layouts and heat managemnt. I am considering those electronic upgrades as end of project decisions. My focus is on re-bracing and re-baffling which is progressing well.

upgrading from a stock CS 2.4 to the CS 2.4SE model.

sdecker doesn’t really have SE-equivalent. The advertised changes were swapping out 13 uF polypropylene + 1 uF polystyrene for 14 uf Clarity SA and 27 uF polypropylene + 1 uF polystyrene for 28 uf Clarity SA. The unadvertised changes were sourcing the boards from FST which reduced the parts quality of the other caps as well as coils (not sure about the resistors). FST were also printed circuit boards instead of point-to-point. It’s also *possible* that the hookup wire on the CS2.4SE was not as good as the original CS2.4.

sdecker kept the 1 uF polystyrenes and used Clarity ESA (instead of SA) to replace the 13 and 27 uF coax feed caps. Probably, sdecker has something *better* than the SE-version although I’m curious to know the sonic consequences of the 1 uF bypasses relative to full capacitance from single caps (ie, 14 and 28 uF). Perhaps Tom Thiel’s trials will include comparisons with and without the 1 uF bypasses.

thosb,

Finally, and there are many on this thread who have better more experienced ears than me, but from what I have heard in my journey so far, "live" comes from tube based amplification.

I always wonder about tube amps myself. The Carver tubed 350 monos keep catching my eye.......But can they handle the 2 ohm impedance?

Thanks for listening,

Dsper

2nd Note;

I would like to hear a pair of CS 2.2 and CS 2.3 models for comparison to the CS 2.4 loudspeaker.  Happy Listening!

sdecker

I share your sentiments upgrading from a stock CS 2.4 to the CS 2.4SE model. Dave Garretson was one of this thread's early contributors on the benefits from using Clarity Cap OEM parts. Having spent much time w/ the 2.4, 2.4SE, 2.7 and 3.7 loudspeakers, soundstage is not a problem.

Happy Listening!

@sdecker
Nope, I didn’t PM you. I’ve owned my 2.4s for only about two years. Tom Thiel coached me through most of my mods. I replaced every part from the binding posts to the driver hookup wire. Sounds glorious. 

@beetlemania

I do remember PMing a couple AG members about my specifics after I posted about my experiences. Were you one?

All your thoughts are well-taken. I perhaps wasn't clear on a couple points you expounded on. Thiel's 1uF bright yellow film bypass caps I didn't touch. I chose the 250V ESA caps for size to fit in the existing XO space for the prior caps.

At the time, at least with the suppliers I looked at, the ESA wasn't available in a 13uF, so I piggybacked a 3uF with a 10uF. The 27uF was stocked. So I never considered assembling what I could to do away with the existing 1uF film bypasses and go to 14 and 28 -- which would likely have required using different 1uF bypasses as ESA wasn't available in 4 or 28uF. I honestly haven't investigated other caps that might work in the XO since then, and I'm sure what you used are a result of deeper research and wider availability of good XO caps since my 2011 upgrade.

What I referred to as ' bypasses' are 10nF, the Vishay-Roderstein MKP-1837 that Humboldt Homemade Hifi (??) recommended for every XO cap application.

My audio friends at the time recommended changing out the XO resistors too, and I promised I would do on my second round, which hasn't yet happened :-(

Can I attach a picture to my posts, or only via a weblink to a photo-sharing cloud service?

@sdecker
FWIW, the CS2.4SE did away with the 1 uF bypasses on the coax feeds, ie, full 14 and 28 uF in single caps rather than 13+1 and 27+1. I am aware of a third-hand report that a 1 uF bypass can have a deleterious effect on SQ (supposedly better to go either higher or lower values for bypass caps). I don't have any information on whether this is related to Jim Thiel's decision to do away with the bypasses. But, clearly, he preferred the sound of 14 and 28 uF Clarity SAs over the original 13+1 and 27+1. CSS apparently has 14 and 28 uF SAs available although the ESA are supposed to be a step up from SA.

My modded boards have 14 and 28 uF values in single Clarity CSAs, the 14 uF bypassed with a 0.1 uF Multicap RTX and the 28 uF bypassed with a 0.22 Multicap RTX. The bypasses improved the "jump factor" and added, maybe, a smidge of resolution.

Buying these parts from a retailer, I would probably get 10+3.9 uF (and a 0.1 bypass) and 18+10 in 630 volt Clarity. Maybe CSA for the bigger value and CMR for the smaller value (for maximum SQ) or all CSA (to save money and space). Jantzen Alumen is said to mix well with Clarity, also.

Regardless, I highly recommend replacing the 2.4 resistors with Mills MRA-12s. You can replace the sandcasts on all boards for about $100. Money well spent. Sonic Craft carries all the correct 2.4 values although you have to mix and match from among the older Mills and newer Vishay-Mills.

Anyhow, thanks for posting about your ESA upgrade a few years back. That gave me courage to try my own mods - and I'm super happy with how it turned out.

Not to turn this into a ss vs tube discussion, just sharing my opinion.

dsper - you are ahead of me as well on your Thiel/digital journey.  Have you thought about a DAC with tube based output?  Also, if you haven't, check out the "taming digital glare" thread and think about all the possible ancillary improvements like power supplies, conditioners, cabling, etc, many believe this all makes a difference with digital and although I have a ways to go, so far I agree.  Also agree with prof's comments above re continuing to recheck speaker placement, including tilt.  Finally, and there are many on this thread who have better more experienced ears than me, but from what I have heard in my journey so far, "live" comes from tube based amplification.  

brayeagle - thanks for the links to the iconclast cables.  I went and spent some time there.  The thing I found most interesting was their claim that "time of arrival" was the missing critical factor, and the main driver behind their decision on how to construct. Way back in the 80's-90's Monster Cable introduced their M1000 series (and later similarly constructed M400's) using three layers of differing wire and construction, with the claim that this equalized "time of arrival". 

I tested the early M1000's against a few other cables (can't remember which ones) in the same price range and the M1000's beat them hands down.  I loaded up on used M1000's and M400's over the next decade and have used them ever since, with results that reveal every iota of change in gear behind them.  Before you rush out to buy any, however, let me add that their cable construction was shoddy and by now probably 50% of the RCA plugs have had to be replaced.  And since the cables are thick this is not always easy.

For those 2.7 fans or owners here’s an old, obscure review of the Thiel 2.7s in a Chinese audio magazine:

https://review.u-audio.com.tw/reviewdetail.asp?reviewid=628

Will require googletranslate. Though I found using the Chrome browser, which offers automatic translation, worked very well. There were very few reviews of the 2.7 (TAS, Secrets Of Home Theater, and an italian one), so finding another is fun.


I love the finish on that pair in the review!  Looks like the same pair, possibly, as the one sent to Secrets.

   As soon as the 2.4SE came out advertising its improved crossover.  Thiel supplied me with the XO schematic and that their auditioning chose the Clarity Cap SA.  I went to PartsConnexion and went up one step to the ESA model, matched pairs, with paralleled bypass caps.  Had to use a 10+3 uF paralleled from their stock rather than a custom-made 13uF cap Thiel custom-sourced.  No other changes to XO (yet?).  

   It was a quick one-man DIY.  Decades as a working EE made this straightforward, if tight quarters.

   Despite the break-in time, it was clear the tightly-matched cap tolerances improved the image focus, and a smidge more transparency throughout the upper frequencies.  At this level of hifi, this was great bang for the $135 buck. 

   I'll add that having both coaxes rebuilt from the ground up at the same time by Rob Gillum post-Thiel collapse was similar to the upgraded, matched-pair Clarity caps, and also improved image focus and transparency a smidge.  But probably moreso because I have so many zillion hours listening to these speakers in the same good acoustic with mostly the same components and cables...

  Do you "share my sentiments" because you've *heard* with your own ears that the 2.4 doesn't soundstage quite as well as the 2.3?