Thiel Owners

Totally agree unsound.  'Time coherent' was never accurately defined with marketing or general knowledge or the physics that create true phase/time coherency like Thiels.  'Point source' is also too broadly marketed, but easier to accurately define.  Ported speakers muddy the definition of both terms, don't they?

After reading the abbreviated Thiel South American history, I sure wish I had waited to find my CS 2.3 and 2.4 in something more exotic than plain old Maple...

   Thiels have been my primary speakers for nearly twenty years now, first CS2.3 then CS2.4 in 2006. A dispute with a new condo neighbor hypersensitive to sound caused me to buy a pair of the new KEF LS50 Meta stand-mounted speakers for substantially less bass transmission between condos. Single coax driver, but 2nd order crossover and rear-firing port in a tiny 12 x 8 x 11" 17 lb box on stands.

   I compared them with my 2.4 when I first broke them in, noted the expected differences, pros and cons, and then parked my Thiels for over a month and listened only to the KEFs. I pulled out the 2.4s a few days ago to remind myself what I've been missing. I'll save the space of comparing the two, but to mention that the immediate and overwhelming sound of my Thiels was 'relaxed' and 'relaxing' musical presentation, to the point of the cliched 'time slowed down' listening to them, a fully 'natural' 'authentic' listening experience. This far overwhelmed all the objective detail differences versus the KEFs I've become skilled at identifying for the past 50 years.

I'll only add my music's bass extension and volumes were moderate enough not to tax the KEFs, the leading-edge speed, and sustain micro-dynamics and detail, were at least as good with the 2.4s, so those weren't factors in 'relaxed' being 'slow' or 'veiled.' It transcended all those individual characteristics.

After all these years, is THIS what full time/phase coherency sounds like once I've been missing it?? That's the ONLY thing I could account for such a dramatic and indescribable difference. I don't think I would have noted this character so blatantly if I had been swapping speakers every few days.

I know a number of forum members have Thiels with other similarly good non-time-aligned speakers. After a long absence, has anyone else had an experience similar to what I describe?

Even though it took me twenty years of listening mostly to Thiels as my primary speakers, I'm amazed I never heard this relaxed/rightness/ease/naturalness/grace so dramatically until after a month of listening to a very good non-coherent speaker.

Why have all the hundreds of 'golden eared' reviewers over the years, I'd like to think many free from industry obligations, and preconceptions of their minimal understanding of engineering acoustics, and who actually DO have good subjective evaluation skills, never (to my awareness) so much as mentioned such a notable difference in musical presentation?? They sure can dissect the individual elements of and between speakers, and over the years Vandersteens and Thiels have certainly been frequently-enough reviewed for *someone* to mention what we notice.

Then again if it took me twenty years of having them in my home without hearing this characteristic as such, perhaps it really is a subliminal subconscious trait, revealed only after years of acclimation?

   Would my and unsounds observations of a more relaxed sound from fully coherent box and cone speakers also apply to full-range panel speakers like Martin Logan CLS, Quad ESL? 
   And for that matter all the single driver cone and box speakers like Zu, Dayton, Tannoy, and many small companies making simple efficient speakers for the SET market?
   There must be a reason I've been a headphone junkie since forever...

@unsound  I'm not sure why any single-driver cone speaker wouldn't deliver reasonably accurate step and impulse response.  Sure, they may be compromised by dispersion, frequency extremes, SPL limitations, but so long as they're free from a crossover and, ideally, sealed or open-baffle (ie no port tuning), I see no reason for them not to mirror the amplifier's time response within the limits of their motor and diaphragm assembly.
   I see why large single-panel planar speakers may be compromised as you describe.
   Headphones are apples and oranges to me.  Two very different and equally valid listening experiences, especially with the relatively recent advancements of higher-end headphones and dedicated amps.  YMMV.  My only point was that nearly all headphones are perfectly time- and phase-coherent, with none of the compromises required by single-driver  or Thiel-like multi-way speakers.

@thoft  as your comment above is aligned with my recent comments of perhaps finally hearing the reality of coherence for the first time in 20 years of Thiel ownership, I'll of course throw in my 2 cents worth with a long essay :-|

I've been going to the big audio shows annually (Montreal in recent years), auditioning in the better brick-and-mortar stores to assess the latest and greatest at all price points and design approaches.  All components, but ultimately the speakers used are the 'gatekeepers.'

After all these years I can recognize great sound, not-so-great sound, and a very 'different' sound.  And hear the best soundstaging and clarity, primarily, that exceed what I'm used to at home.  But every time I return home with a weekend of high-end audio fresh in my head, there's a certain 'rightness' to the sound in my room that more than makes up for the improved specific attributes of various systems I heard at shows or showrooms.  I can focus on the attributes my rig doesn't do as well as the uber-systems, but that doesn't alter the listening satisfaction.

This does prevent major upgrade fever, and also makes it very clear when I do make a tweak for the better.  Some of this is long-term familiarity with my electronics and room acoustic, but from recent posts, I think a lot has to do with my 2.4s presenting my audio signals out of the power amp more realistically than the mostly non-coherent speakers I'd been auditioning.  IOW I'm not missing the coherence when listening to other speakers, but relaxing back into it when I return to coherence.  

But this seems a long-term thing.  I don't recall the Thiel or Vandersteen or Zu rooms sounding 'relaxed' or even that great, but I also don't hear this coherence 'difference' when comparing speakers back and forth.

@bellesfan  I still have my 2.3s and have been listening primarily to my 2.4s since 2006.  I can tell you despite the similar external appearance, there are MANY changes between the two speakers that make them very different.  Some tweaks may be made to the 2.3 XO, but you'd be nowhere near to a 2.4.  If you want the full list of changes I can PM you, but it might depress you...

   For years I've been lamenting that "New Thiel" seemed to have entirely thrown out all the info on "Real Thiel's" comprehensive website.  For me, that included the page of zilllions of links for every speaker made: technical supplements, reviews, owner manuals, marketing brochures, all the way back to the Model 01.  I don't know why I didn't do this years ago, nor have I seen anyone else on this forum bring it up.  I simply brought up archive.org ("the wayback machine") and looked for Thielaudio.com. 

Everything has been saved!  I just picked this one url and I can get to every pdf, paper, review (that's still on the web), even five open positions for hire.  There were many dates of different updates, but rather than crawl through the whole website history I'll offer up this link that seems to recreate the 4/12/2010 capture of the entire website.  Hope it works for the rest of you via this this.

https://web.archive.org/web/20100412030537/http://www.thielaudio.com/

  It's like finding out a long lost friend isn't dead after all...

To tomthiel and pieper1973.  We had discussed this some time ago, but a reminder that my CS2.4, bought from the original owner after one year, are SN 611 & 612, and have the entire Lexington masonite XOs and best parts of the era.  Seems unlikely they'd use Asian XOs at 250 and switch back to Lexington XOs at 600.  My 2.4s were nearly brand-new and certainly unmodded when I bought them.

Speaking of modded, I revisited what I had done around 2010.  I used 250V Clarity Cap ESAs, a 27uF, and a 10uF || 3uF.  For the 1uF bypasses I kept the existing Thiel bright yellow Elpacs in place.  And added the then-recommended Vishay MKP-1837 10nF bypass across both cap combos, improving the ESA sonics that smidge more.  The CSA versions were not yet available at that time AFAIK.

I'm not losing sleep over not using 630V, subbing in CSAs, or keeping the Elpacs instead of using a much-better 1uF bypass, but by now others have done more and may suggest improvements.  My guess is finally getting to Mills resistors would be a better use of my time.

 

ESA Sound: Similar in overall character to the Clarity Cap SA [used in the 2.4SE] but with more clarity and therefore a fraction more spatial. Like the SA they could still do with a bit more transparency but with a small capacitor placed parallel to the ESA this can be improved. The ESA also has a slightly warmish presentation and also benefits from making a total value using about 90% Clarity Cap ESA and about 10% Mundorf Supreme. This opens up the top end just nicely without altering anything else. Good overall qualities and an upgrade from the standard Clarity Cap SA.

CSA Sound: The tonal character of the Clarity Cap CSA has in common with all Clarity Cap capacitors that is well balanced and never fatiguing. The CSA shows a pleasent intimacy combining the clarity (pun intended) of the ESA with the smoothness of the larger MR. Relatively speaking, I actually found the step up in sound quality from the ESA to the CSA to be greater than from an MR to a CMR. Both the CSA and CMR use Clarity Cap's Copper Connect Technology but it seems to have a greater effect on the SA range than of the MR range. Maybe it's easier to improve lower down the scale than further up it, I don't know, but that is how it cames across to me. Anyway, in direct comparison to the CSA the ESA sounds a little rougher, the CSA seems to produce a more civilized image that is at the same time more neutral. "S" and "T" sounds that were first maybe a little bit rough around the edges with the ESA (I am being very nit-picky here) become free from grain with the CSA. I also found the CSA to mix extremely well with the Jantzen Audio Alumen Z-Cap. A mix of a minimum of 20% Alumen Z-Cap with the rest Clarity Cap CSA enhanced realism of space and lushness of tone. They blend together seamlessly. All in all the Clarity Cap CSA is a well balanced, neutral capacitor that is a welcome addition to capacitors in the lower price range.

I've made a point to have "Lincoln"-like friends to evaluate changes in my own system over the decades.  Changes I (and other audiophile friends) may be too caught up in the minutiae to make an unbiased evaluation.  I think half the reason the Lincolns are so useful is they're excited to hear 'real' hifi reproducing music that they can better focus and more enthusiastically assess, free from what they 'should' be hearing.

What does your experiment say to the common knowledge (?) that time/phase coherence can only be achieved using first order XOs when processing in the analog domain??

Just catching up with the past week of posts -- about 2.4s. Surprised to learn this was Thiel's lowest-volume speaker, building on the successful 2.3, with a good economy for the first 5 years of production when most would have sold, and a still-committed dealer network.

As a point of reference, mine are SN 611 & 612 and almost definitely have the original XO: wooden LF & HF boards (literally) hand-wired with Acousti-Coils, AEON electrolytics, bright yellow Elpac 100V 1uF 5% polystyrenes (?), Erse 100uF 100V electrolytics, Xicon resistors, and a Solen PA-MKP-FC in the LF XO. I believe they were AEONs that I replaced with Clarity Cap ESAs some years ago in the coax feed. Rob Gillum built me a new pair of coaxes a couple years ago, so I'm sure I'd be most of the way to these speakers' potential once I replace the resistors.  *Most* of the way: I know how far some of you have gone with all the ancillary parts!

When I bought these used from agon in mid-2006, I had checked with Thiel who told me these SNs were early production units with the previous woofer that was later updated, though sonically identical. Never followed up about that, but I'm sure buried in my paperwork or emails is the date of manufacture of these speakers.

Wow Beetlemania, you're my kind of audiophile. The few times I posted similar details, and the proper test engineering of listening and evaluating each set of changes, then ranking them, I've been met with crickets. As such, my post you're responding to was minimal.

I do have 0.1uF bypass Multicaps across all three ESAs, and my 13uF coax series is a 10uF || 3uF ESA. (These are in addition to the Lexington Elpacs I mentioned that remain in place) I'm sure there are all variety of better caps by now that improve on both CSA and ESA; that ship has sailed.

Fair point to replace the electrolytics due to loose tolerances and drift. I'll look into the coils and order the resistors. Thiel supplied me with the schematic for the HF XO, but don't have one for the LF XO, though it should be simple enough to figure out. Anyone who has that diagram I'd appreciate it in a PM.

Does anyone know about the changes to the 2.4 woofer that were apparently made after my speakers were manufactured?

@jafant  I'll be interested to read your impressions of the SA11S2, though not sure how much detail you'll post on a speaker forum.  I auditioned one at home for 30 days when they were newly released, and sent it back...Perhaps we should compare notes offline after you've had ample time to get its measure.  Don't want to bias you or anyone else about their electronics!

Thirty days from now I expect you'll post equally thorough impressions of this player.  Or at least PM me.  YMMV.  I hope!

As jafant is the original poster of this 199 page thread, and specifically asked me to comment here about my impressions of a disc player he purchased, I'll respond.  I'm not hijacking the thread, or he's not telling me I'm not, but my long-winded reviews rarely get comments.
I auditioned the Marantz SA-11S2 for a month in 2009 as an open-box unit from Music Direct.  For similar reasons to you: how a relatively expensive SACD player can sound, how the CD section sounds, how the transport sounds vs my own, and the overall impression given Marantz's reputation for build quality and SACD playback.
My primary comparisons were to my CD playback of a Madrigal-updated/upgraded and my slightly modded Proceed CDD transport via a Kimber D60 to my Great Northern Sound substantially (and cleverly) modified Bel Canto DAC2.  SACD was compared to my Yamaha DVD-S1800 universal player: it plays SACD natively in DSD from laser to outputs so you do hear the purity of the format, but uses probably $10 of parts to do so for the 2-channel mix.  I threw in my analog rig using the 'same' material as a reality check.

Michael Fremer did a full review of the unit for Stereophile and I remember agreeing with most of what he said (as I usually do), despite his requisite sugar-coating for the magazine.
In short, with CDs, there wasn't anything the Marantz did notably better than my rig, and a number of areas where it fell short.

With filters 1 & 2 I found CDs to sound slurred and muddy.  Only 3 sounded OK.  Compared to my stuff, the lower bass was amped-up; the mid-bass was slower, underdamped; slight differences through the midrange that didn't favor either; it was a draw in HF textural resolution, but the Bel Canto was better with HF decay naturalness.  Soundstage width was about the same, but my rig did dimensionality better.  My rig did the PRaT thing clearly better, but the Marantz didn't have its external clock option.   The Marantz didn't have the speed, resolution, and clarity of my stuff, which matched the Marantz for smoothness, lack of grain, and freedom from long-term listening 'digital fatigue.'  Overall, a warm frequency balance does not an 'analog-sounding' CD player make.
The player sounded marvelous with SACD.  A mostly-different signal-processing path, but Marantz took advantage of the intrinsic advantages of DSD over PCM: very easy decoding, much higher resolution than redbook; the care in mastering the SACD layer; the smooooth sound of SACDs correlated with the smooth glossing over of CDs with their PCM decoding.  At the time, my direct comparison was my universal player, which commits only sins of omission.  The Marantz took the purity of native DSD of the Yamaha and put it through a good output section (at least) where the dynamics and details could and did shine through.  But the bass was still bloated and slow.  The soundstage wasn't nearly as holographic as I've heard from better and/or newer SACD players with the same discs.  There was some resolution left on the table.

Their custom M-1 transport and SPDIF processing (digital out) was no better than my Proceed.  Far worse, in that for my full audition period I always got a ton of read errors across a variety of discs that usually required power-cycling the unit.

The player was unnecessarily big and heavy, to justify its high end pretensions?  The front panel ergonomics were awful, form over function.  Why is the external clock selector on the front panel?  Why isn't the polarity switch on the remote?  Why is the power switch -- to be left on most of the time -- front and center?  Why are the transport controls split 6" apart between the two sides of the raised center front panel?  For such a big unit why is the display so tiny to be unreadable unless you're on top of it?
Granted, my Proceed (essentially a Mark Levinson No. 37) excels at ergonomics, display visibility, programming flexibility, responsive disc reads, but I wasn't willing to take a step backwards when the player as a whole did not do $3500 worth of improvements for me.  Any, really. 

I doubt that new opamps and replacing the 6 fuses is going to change the overall character of the player as I've described.  If you got this for a few hundred bucks and have a bunch of SACDs, it may be worth it, but for MY sensibilities versus MY gear it was a disappointment.  Twelve years later I know there are better units to be had for similar prices.

Be careful what you ask for from me!  I now return you to your Thiel speaker forum...

Well the SA10 is twice the price of the SA-11S2 and designed nearly a decade later, so I would certainly expect it to sound better, especially following the critical feedback Marantz got from their relatively murky sonics back in the day.  The front panel ergos are improved, there are digital inputs, their in-house transport is two generations newer, and PCM is immediately transcoded to DSD.  I'd venture to say these players could well be sonic apples and oranges. 

You found the SACD format as a whole to be a "strange interpretation of the music" or Esoteric's playback of it?

CD playback should now be as good as the format allows on any player over $2K.  Low-rez PCM ought to have been figured out by now.  Different flavors and approaches, sure, but pulling everything off the CD should be understood -- I may be wrong.

I spent a day listening to the dCS Puccini SACD player nine years ago (vs other units, including my own DAC FWIW): that was the best SACD playback I've yet heard, and I'm sure a decade later newer designs sound as good for less money.

   As good as the Sansui AU9900 may have been / was in 1975, amplifier technology is now so many generations of sound quality beyond that as to make it likely unlistenable compared with a Classe CAP-101 or similar.  How is the Sansui much different or any more 'fun' from the Pioneer SX-1050 that's only a couple years newer design?
   I owned and/or listened at length to similar Pioneer and Sansui amps of the era.  I bought an Advent 300 receiver to replace the Pioneer and, aside from power output, it blew them both away in every sonic metric.  
   Old top-of-the-line Japanese electronics are usually really well-built and generally reliable, but today - in most cases - they are better to look at than listen to.  Their best FM tuners excepted, with some new parts...

Professional tape machines suffer in modern comparisons because they're all at least 25 years old, with technology and electronics that are even older.  Whether multi-track or 2-track mixdown, most of the mechanical parts are worn-out and unavailable, the electronics are also worn-out and old-school parts and circuit designs.  Few remember how to maintain and calibrate (daily) the studio decks.  Finding decent tape is a challenge.  I'm sure only a handful of studios worldwide have an analog recording chain that's working as well as it was in 1980.  And what artist wants to pay the far greater price to record true analog?

I sure wish it were otherwise, as I'm sure if analog studio gear had kept pace with everything else the past few decades, the choice of all-digital for ease of recording, near-zero cost, and improving-yearly sonics wouldn't be quite as stark.  Ironically, when I see a current album was recorded AAA, I'm concerned about the health of the entire analog signal chain and their intentions when the best digital gear can make recordings that will exceed worn-out analog recorders and signal chains :-(

I've seen the recent revival of prosumer (and pro) 2-track R2R for the ultimate in home playback, but most of them are fully redesigned (playback) electronics and rebuilt or remachined mechanicals.  And I'm never sure how and from where they're sourcing their not-inexpensive tapes...

ydjames   With the praises you heaped on the QLN Prestige 3, and the near-identity of your upstream gear with that of your 'close friend', it seems a trip to his home with your CS2.7s to compare would answer a lot of questions for you, your friend, and all of us here on this forum!  

Wow, I can't even let a week go by and this thread gains a couple more pages to catch up on...

I want to be the first (?) to agree with TonyWinga's 7/29/21 post of optimizing his CS6 that they parallel my experience with 2.3 and 2.4, and cover most of the basics for setting up any Thiels.

To TomThiel's 8/2 post that 2.4 XO production went to FST around SN 220-230 is at odds with my 2.4 SN 611-612 clearly having Lexington boards & parts as discussed here earlier -- unless you were referring specifically to 2.4SE?

My 2.4 are 6' from the back wall and either side wall, 8' apart, 9' to the ideal listening position, and have a smidge of toe, <10 degrees.  While they're 6' to the 'real' back wall, they're 3' to 'interruptions' like an open stairwell and my stereo rack.  The room is an open floor plan to other 'attached' rooms, 8' ceiling, thick pile rug.  So overall very good acoustics for Thiels, with no reflective boundaries anywhere nearby. 

But it does create a lumpy low bass room response below about 80Hz.  Indeed, 25Hz is the same 0dB reference level as 1kHz.  This was 'reinforced' when I recently bought KEF LS50 Metas, whose output drops steeply below 80Hz.  So in many ways their bass is smoother in my room as the low bass is MIA and not exciting the room nodes.  Luckily, a lot of music has little or no bass below 100Hz.

I was following with interest the thread a couple weeks ago about how Thiel's moving from sealed to radiator/ported woofers threw off the low-frequency phase coherency by 360 degrees. How does this make for a "coherent phase" loudspeaker if so much of the frequency range isn't aligned at all?

Stereopile always makes frequency response measurements of port vs woofer. My 2.4 shows that above 100Hz, the radiator's output is 15-20dB below the woofer. So if I'm playing music with no bass content below 100Hz, do I have a reasonably coherent phase speaker?

And as all Thiels were no longer sealed after the late-90s, why do their spec sheets state "Phase Response: +-10 degrees"?? (or 5 deg with 2.3 & 2.4)   Given Thiel's comprehensive tech data, why is this so vague?   As it states no frequency, is it unspoken that this is only valid above the woofer's passband? The clean-decay step response plots suggest at least the 'time' coherency to be true.

My 2.4 brochure states "Completely Time and Phase Coherent." Then it states the 'time' portion is from the slanted baffle and the 'phase' portion is the first-order slopes *between the drivers* -- is this to suggest that what happens outside the XO, ie the bass loading, is 'outside' a driver rather than 'between' drivers??  And therefore low frequencies are inapplicable to the "complete" phase coherence and +-5* spec?  That seems very un-Thiel-like, and I'm sure someone long before me would ask that question!

I'm sure someone on this thread has the necessary acoustics (or marketing-speak) background to offer insight here. All my pre-Thiel speakers were sealed so I'm finding this, uh, interesting...

tomthiel et al: "reflex bass is the industry standard" but none of the current manufacturers are claiming their speakers to be "Completely Time and Phase Coherent."  My longwinded observations and questions may be better suited to audio asylum.

@tomtheil Not to put too fine a point on it [although it seems I did!], but I have most of the hardcopy 'glossy' marketing brochures for 2.3, 2.4 and the 2000s entire Thiel line.

The 2.4SE brochure's lead headline under "Features and Benefits" is "Completely Time and Phase Coherent" and repeats that in the text.

A text printout of the CS2.3 web page states "As with other THIEL speakers, the CS2.3 achieves complete time and phase accuracy for very realistic ...".

The CS2.4 brochure in the center section of bulleted features "Completely time and phase coherent for greater realism" and repeats the same sentence in the headline of the text that repeats it again and its benefits.

A four page glossy full-line brochure from 1/2011 makes the same statement at the top of their bulleted features, as does the CS2.4 "New Product Press Release."

So perhaps the marketing folks took liberties that Jim would not have approved of personally and technically?

I'm uncertain what you mean by the "phase shift problem evaporates" when the "bass extends below the program limit." What is the 'program limit'? There's essentially no 'real' bass below my 2.4 passband of 33Hz. It's the range between 33 and 100Hz that the radiator is fully active that it seems there is the phase shift.

Please don't anyone take this as a critique, only critical thinking. Just in the last few days I've reconfirmed how the relaxed and lifelike presentation of my 2.4 exceed all the lesser benefits of my recent KEF LS50 Meta purchase, and put them back into the big rig indefinitely.

@thielrules  I'm not sure many of us could differentiate a 'coherent source' Thiel from a 'conventional' speaker with standard A/B testing (blind or not) over the course of an evening.  As I related a few months ago, I bought Thiels (2.3 then 2.4) as they checked so many boxes for both design and immediate sonics.  Their coherence was mostly an academic advantage to this engineer.  It was only after a few months of listening only to a good non-coherent speaker in place of 20 years of Thiels in my familiar acoustics and electronics that reinserting the CS2.4 into my system created a profound psycho-acoustic improvement.

@tomthiel  OK, I'll accept that, that the ported bass results in a fixed 1-cycle lag from the radiator, hence phase coherence remains intact throughout the speaker's entire bandwidth.  And time coherence is only impacted in the lowest frequencies where the passive radiator is most active, below 100Hz in my 2.4 instance.  And yes that's a helluva lot better than most other speakers that go through all sorts of phase and timing shifts at each crossover point, as Stereopile plots show, dismissed as 'optimal crossover design' as 'each driver smoothly hands off to the next.'

@brettmcee  Really good post above.  I've done and accomplished over a lifetime of hardware and music nearly everything you praise (except reel-to-reel and Schitt, perhaps at my loss).  I'm no longer a digiphobe now that *good* digital can be very good, but use it for what is best and get into the analog domain quickly (knowing most vinyl from the past 20-30 years was recorded digitally, often with awful gear by today's standards).  Achieving system synergy with the variety of combinations or hardware, room acoustics, and your ears, is the end game.

@big_greg
Interested to read your adding CS2.3 to your KEF Reference 1. I recently added KEF LS50 Metas to my CS2.3 and CS2.4. Both of us are new to our new brand it seems, and we both have ’enough’ watts for all speakers. While the Reference 1s are 5x the price of my LS50s, it seems there’s enough to warrant comparing to the 2.3s.

One could argue the 2.3s are a floor-standing Ref1 with aluminum coax mid/tweet in a waveguide (tho the uni-q far more technically advanced) and vented aluminum woofer, and their (projected) current pricing probably similar to each other, though of course the Thiel time/phase coherence is the biggest design difference.

I’d be curious how your listening impressions develop, and surprised if you find the 2.3s overall so much the better speaker to the point of selling the Reference 1s! Certainly elements where the Thiels will have an ’edge’, especially once you grock the benefits of full coherence.

I’d add that the 2.3s aren’t particularly bright in the sense of a rising treble/tweeter output, but have an upper midrange that is (to exaggerate for clarity) too forward, unrefined, unruly, and tough to tame, the ’edge’ you describe, so aiming them straight ahead is best, away from walls. This doesn’t really show up on various frequency response plots, but is the biggest difference to the 2.4s, where that trait is completely tamed. The 2.3s image better than the 2.4s and I wonder if you find them better than your KEFs in this respect. (I find my LS50 Metas ability to throw a soundstage into the entire room much better than my 2.4s)

I’d say the key 2.3 setup parameter is their distance apart from each other versus their (minimum 8’) distance to the listener. I find my KEFs sound best in the the exact position I’ve set up my 2.4s for the long-term. Also tweaking the distance to the back wall for some bass reinforcement as needed. Have fun!

I discovered the benefits of spikes in the same way Tom Thiel did, though likely even more exaggerated with my then Boston Acoustics A200 speakers.  These were wide and tall floorstanders, but only 7" deep, with a simple plinth only 4" deep.  The 3 drivers were widely-spaced vertically.  So the woofer rocked the plinth substantially on the carpet, which levered the tweeter back and forth (relatively) substantially.  When a friend suggested using aftermarket screw-in spikes, the entire soundstage (such that it was) snapped into focus as there was now zero rocking and the drivers sonically 'aligned.'

Despite my subsequent CS2.3 and 2.4 having a far deeper base, I still notice the benefits of their included spikes -- on carpet over slab.  I had the 2.4 outriggers, but sold them as their primary purpose seemed to stabilize the speaker from being knocked over by large pets or small kids.  Moving the existing 2.4 spikes a few inches outboard in each direction had no audible sonic advantage, only less-visible low-lying arms to trip over.