Thiel Owners

James - a thought from Thiel history for you. I take interest in how brands associate with other brands. Partly in play is dealer synergy - dealers tend to carry brands that go well together. Sometimes designers align with other designers for shared approach or desired outcomes . . . Thiel’s brand associations grew somewhat over the years, but centered on some brands that get regular mention in this thread: Krell, Mark Levinson, Bryston, early Classé and Threshold.  For the record, McIntosh never came on Thiel’s radar. Nothing negative, but nothing ever presented itself.

For myself, my first aha moment when I learned that reproduced music could be every bit as involving as live music involved McIntosh. As a singer-songwriter-student I was immersed in music, and playback was mostly a tool for production and for learning. Then one day I went to lunch at a faculty community house at the edge of campus. After lunch we all sat down to absorb a newly released jazz album, followed by an appreciation and discussion of musical and sonic merit. It was 1967, I was a freshman. These guys opened my ears and my mind.
The only piece of gear I vividly remember was the pair of chrome amps with their glowing tubes. When asked, Brother Stan said they were McIntosh - I don’t remember the model, or the turntable or speakers. I do remember the musical magic and the adjectives 'lush and delicate'.

tomic - that trip was not in my time. I have read Dick's article(s) that likely resulted from such a trip. I did know about Dick's visit to the Thiel factory. I knew Dick from Havens and Hardesty when they were one of our best and favorite dealers. They were an enormously successful Vandy dealer and RV didn't allow his dealers to take on Thiel - and Dick said 'get over it'. DH and RV were best of friends and we loved DH too. His explanations were so lucid and clear! The good, they die young.

Prof - your information is correct. As a company we aimed our products at living-room listeners. Thus the relatively high cost of our enclosures. We assumed grilles would be in place for listening. Over the years, our fabrics became more sheer and less audible, culminating in perforated metal grilles, which are very transparent.
To various degrees, fabric reduces amplitude in the 1.5 to 8kHz range by as much as 1dB. That’s pretty huge, considering that sophisticated listeners can register 1/10th dB differences when sustained over a broad sonic range. The bare speaker will sound more aggressive, especially in less-treated rooms.
To another point. Thiel’s grille frames were used as a significant mitigation to cabinet edge diffraction, and sometimes as wave guides to shape off-axis dispersion. In the case of a very dead room and a listener preference for the additional brightness content, we highly encourage taking the fabric off the frame and using the frame for its engineered purposes. I have also noted wave propagation effects directly on the baffle surface which are tamed by the fabric itself (on models with fabric touching baffle.) Generally speaking the grille is a significant engineering element and removing it undoes significant design effort. I’ll add that many of the long-standing criticisms of the Thiel sound (up-front, in-your-face, tizzy, harsh, etc.), directly result from removing the grille.

Let’s side-step to your model 02s. That model preceded our knowledge and attention to most of these diffraction and wave-guide considerations, but the frequency response is more accurate with grilles on (and overall performance is probably a toss-up. The Renaissance 02 reworks the grille for considerably higher performance while retaining the general aesthetic of the original 1976 design.

Thiel's US distribution began in the mid-Atlantic whereas VS on the West Coast.

thoft - any answer to your question of amp / speaker / room adequacy is by nature incomplete, often in danger of mucking things up more than clarifying them. The equation is very complex. Many combinations work OK, and the pursuit of "better" performance is fraught with trade-offs including cost. I know it sounds trite, but if it works for you, that’s the goal.

Now for my personal take. I have outlined my amps and rooms here before, and my MO of playing the next-album-up for my evaluations. That album often works all day, and I hear cuts in the background, in intensive listening, standing and sitting, in measurements, and with different amps, cables, circuits, treatments, etc. I say that significant, recognizable aspects of each amp are audible - and they may be important to you, or not.

Your Adcom 5800 is a big brother to my little Adcom 5300 (at 250 vs 80W/C). They use MOSFETs in the signal path which lean toward tube sensibilities. I have no direct experience with your amp and can’t judge anything about your setup. But Nelson Pass either designed it, or was part of its design development path. Nelson is a world-beater, and his amps deliver high current, which Thiel's demand.
If you enjoy the game, you might find a way to borrow or audition another contender for direct comparison. The game takes time and costs money. At some point we might consider letting musical enjoyment guide us.

Prof - I suppose an 'ultimate' solution would have nothing in front of the drivers, except possibly a phase plug at the apex of the tweeter. The bare baffle then needs propagation control. We used splatter paint and fabric on baffle (in my time) to break up glare. Later, the perf metal may have performed that function. I like my new Ultrasuede on Felt solution. 

Once a designer decides to protect or otherwise hide the drivers, then it's a dance of interacting variables. The user might choose differently than the designer, but often lacks knowledge of the trade-offs. 

Thoft - to augment unsound’s point - an aspect to consider is voltage sensitivity of a speaker in a room. I like that you can listen at 3/4 volume setting. Many preamp designs lose performance as the volume setting decreases. Often the criticism that a speaker doesn’t perform well at low volume is less a characteristic of the speaker than it is of the amplification driving it. Of course our ears roll off in the bass and treble at lower volume, so speakers with a bloated bass will sound "better" at lower volume. But the preamp considerations are a significant determinant factor. PS Audio’s ’Gain Cell’ solution side-steps the issue and sound "the same" at any volume setting. Such a puzzle. Nice solution. PS's moderately priced Gain Cell DAC-Pre is my go-to preamp for this reason among others.

Pops - good memory. I’m working on a response for this forum. Listening Room was a very early dealer who remained a very strong supporter for a long time. BTW: Don Hoatson’s grandson, who grew up intertwined with The Listening Room is continuing that business on the Eastern Shore.

When is indeed a good question. As many of you know, we were making it up as it came and there was no clear launch date.

1976 is the short answer, and pops gets a star.

As our intentional community sought a common enterprise so that no one had to get a real job, we considered hi-fi and stage amps as possible additions to my Conceptions Studio which produced custom and sophisticated art-craft. My first love was guitar-family stringed instruments, plus furniture and other artifacts. Walter Kling was also involved in the studio. We all decided to fund Jim through 1975 to explore and develop an electronic product that was salable, scalable and unique. We thought it would be an amp or pre-amp. His first patent would later be a unique head amp, and it turns out that his equalizer circuit was ahead of its time. He was a natural circuit guy. But we settled on a speaker because we thought we could make more of an impact and better differentiate ourselves there. We set about creating an internally powered speaker along with an 8'x 8' powered folded horn subwoofer, both of which we abandoned because making a new market is such a tall order for a new, inexperienced and self-funded company. So Jim developed the model 01, an equalized 10" two way that was indeed unique and successful.

Early 1976 we sold our limited studio production through friends, word of mouth and home-based gurus, which led to our first ’real’ dealer in nearby Frankfort KY which had a hi-fi department in an appliance store. They sold a lot and suggested we add a model 02 for more audiophile appeal. Jim reluctantly complied, which opened a door to a marketplace where we found our home.

The summer of ’76 Kathy and I moved to Maryland for her further studies in psychology. While there she attracted dealer interest. I’ll go with Pop’s assertion that ’The Sound Room’ outside Baltimore was our first legitimate hi-fi dealer. Kathy took on a good half dozen dealers in Virginia, Maryland, Pennsylvania and New Jersey. Many of those pioneers remained productive long-haul dealers for decades.

Selling speakers requires making speakers. I set up shop in Maryland to make equalizers and returned to Lexington one week per month to work with Walter in the shop. Fred Collopy was modeling our start-up for an independent graduate class. Every penny went into more parts and supplies. I bought a van to haul speakers back east every month. We had more demand than we could handle and developed a plan for sustainable growth.

We signed up for CES- January 1977 in Chicago and went big with an outboard hotel suite that showed considerable sophistication. I remember a (British) industry guy speculating to amused listeners that we were supposed be barefoot and pregnant back in Kentucky. That moment became a cogent reminder to keep our professionalism high and avoid reactionism. "Don’t tell ’em, show ’em".

Working 01s and 02s with static prototype of the 03, a floor-standing equalized 3-way expansion of the 01. Nothing about phase or time at that time.

Good show. Good response, including a German distributor which led to better European than US distribution, and got notice from Lyric Hi Fi who was a bellweather at that time.

Back home we decided that the 03 had to be more than just another market entry in a market that was way more crowded than we had imagined. Jim focused on how much effort went into managing time and phase in his amplifier circuits and asked why was it OK to dismiss that at the end of the chain. Many serious experiments turned into a year and a half of unrelenting work to develop the first coherent full-range transducer that we knew of. Turns out that Richard Vandersteen was on a similar journey in California, but neither knew of the other’s work.

The success of that 1977 CES led us to commit, incorporate and borrow start-up funds through our and Kathy’s parents’ second mortgages. Failure was not an option.

The standard answer to when Thiel Audio began is 1977. This early history including The Listening Room predates that date of incorporation, which wouldn’t have happened without the early enthusiastic market support we received.

 

 

Thank you JC for the link to Thiel Audio’s incorporation docs. To correct the record, it seems that Thiel Audio Products Company didn’t incorporate until 1985. So those early borrowings and growth were done under the auspices of Conceptions Studio. Memory has holes. Details fade, but the broad brush still paints true.

 

 

JA - Don died a few years ago. His grandson Mike who grew up around the business is carrying it on with the help of Don's wife and brother.

Prof - I think that's the same site that picked up the domain when New Thiel went bankrupt. Note there's no Thiel content on it. It is (or was) owned by a Swiss gambling consortium who harvests contacts via any which way.

Is there a Thiel Blog being maintained somewhere?

Prof - I had not known about that Thiel blog. I don't know who might be funding that site. Someone here may be able to look behind the curtain and see. Otherwise, the person who comes to mind is Rob Gillum as an adjunct to his Coherent Source Service undertaking.

The dates go from just after Jim's death to just before Kathy sold the company at end 2012. Those people are the real operatives saying things they would say, albeit with a few typos and some editorializing. I speculate it may have been Gary Dayton's project. Note there are nearly no responses and that the external links are broken.

Regarding the thielaudio.com site - Ted Green of Strata-gee.com looked behind that curtain a few years ago and indeed, it is some sort of fishing expedition. Note that the external links are broken and that pictures and references are not of Thiel products, but rather generic drop-ins. The odd workings of the webosphere.

At Coherent Source Service, they were effortless and pure. Rob had a great amp driving them, but I don't remember what it was. The flat-front drivers of the original 7 address a real problem of cone drivers. The sound of the upper driver falls into the cone cavity of the driver(s) beneath, creating a particular hollow congestion which I have identified both sonically and in measurements. The 7 is free from that problem. Even though Jim improved the technical driver performance for the 7.2, Rob and I both found the 7s more musically enjoyable in his small room where we could barely get 8' away.

I am told that Jim was working on the 7.3 after the 3.7, including a refinement of the 3.7/2.7 upper coax, modified to more readily cross over to the 6.5" CS7 lower midrange and CS2.7 -  8" woofer. The 7.3 would certainly have had the flat-star lower drivers, which address that cone cavity problem. Plus each generation of his drivers stood on the shoulders of its predecessors. Imagine that speaker. But, the 7s or 7.2s are pretty good in their own right. If a pair came my way, I could live with either one of them.

Prof - check.

Roxy - I have pasted together a fairly valid narrative, albeit with large vaguenesses and some holes. Some of the story is recounted in Ted Green’s Strata-gee.com interview with me from around 2018; we’ve also covered some in these 220 pages. A full reckoning would take pages, so here are some highlights.

For lots of reasons, Thiel Audio had been slipping for several years. Jim had kept his cancer secret for 5 or so years, but it affected everything. It’s amazing that he produced such magnificent late work while fighting his terminal illness.

Jim died in September 2009, about a year after introducing the breakthrough CS3.7. He had also developed much of the CS1.7 with a star-plane woofer like the 3.7. But the 1.6 was still young in its life cycle, and he went working on an upgraded CS7.3 coax. I’ve been told (but don’t really know) that driver took the 2.4 passive coupling to a higher plane. Let’s say there was strong work in the pipeline and he hoped to attract a buyer with that work as part of the package. For lots of reasons that didn’t happen.

I’m not sure when Kathy had taken sales to Crutchfield, but I do know that was a huge bone of contention between Jim and Kathy. I don’t know much more except that the stellar Thiel dealer base was gone when I checked in. That was September 2012 at the finalization of the 2.7 which had been co-developed between the long-term Thiel team and a Canadian engineering outsource. That product would not have come from Jim, but was relatively easy picking using the extant 3.7 coax and nearly extant 2.4 woofer in a quasi 3.7 cabinet. I congratulate that product, but it doesn’t really fit his MO. Jim’s natural sequence would have been to develop a 7.3 which would have a 3.7 style coax, possibly with a passive coupling and certainly with smaller diameters (enabled by crossing to larger lower midrange) capable of upper extension past 30K, plus all star-plane lower drivers. Then, trickle-down that driver technology to the 2.5. My conjecture is he would have held by our normal numbering system rather than skipping to the x.7 nomenclature.

After Jim died, and the dealer base was limping, Kathy tried to carry on, but lacked the internal design-research chops. The development cost for the (relatively simple) 2.7 was over a $ quarter million, which was unsustainable for a rather lean company. On my 2012 visit, the factory was a ghost town with perhaps 5 people and no speakers being built. Kathy went shopping for a right buyer with considerable help from industry insiders. No proper buyer was found. The lookers either lacked belief in Jim’s design goals and/or saw and knew the extreme difficulty of actually pulling off true coherence. In 2012 a broker presented the New Thiel buyers and a deal was struck.

At that time something could have been salvaged from the legacy, but they lacked any audio experience and took every wrong turn in the book plus some of their own. Within weeks the last of the old team had been fired or resigned. In the five ensuing years, they went through 5 executive teams and spent about $10M on a sad circus.

Anybody can second-guess anybody else’s judgement. When the dust settled it was just a very hard job suited to a team of very astute insiders aligned with Jim’s goals and vision. None of that materialized.

Adding to unsound’s comment - if one amp does drive your small room, stereo mode "sees" twice the impedance of bridged mode. This class A/B amp will have less distortion and sound better in stereo mode. I suggest a direct comparison and tell us what you hear.

FWIW - there about 1000 pair of 7s and 2500 pair of 7.2s, compared with 3000 pair of 3.6s.

jon - you’re in good company. Most engineers align with Dr. Toole in claiming phase coherence doesn’t matter. That opinion is based on observation of double-blind testing. Note that Jim Thiel began his audio journey as one strongly in the camp of empirical / engineering driven mind-sets and choices. The coherence thing wasn’t an accident, but its existence has elements of accident.

Before introducing the 01 in 1976, we experimented with many types of transducers. Among them was a sphere covered with 1/2" tweeters with enough combined surface area to support full range reproduction. The predicted sonic nirvana didn’t happen. Over a period of months, we compared transducer types to determine our eventual platform / approach / solution. To shorten a very long and involved story, we needed a full-range coherent source as a reference - call it an inverse microphone. The Coherent Source concept began as a laboratory standard rather than a product idea.

That rightness or ease or naturalness or grace in the coherent source- was unmistakable. Coherence also unveiled myriad problems previously masked by phase scramble. A book could be written about the psycho neurology involved in interpreting sound, and the priorities and effects of "real" vs "scrambled" sound. People here have asked whether phase coherence is heard directly or part of a system of scrutiny of all factors involved in the transducer. No easy answer, but after experiencing coherence, we never looked back.
Presently I am working with the 02 as an accessible workhorse for testing and comparing various technologies. The 02 is a polarity-correct second order system (as were its successors - the entire SCS sequence.) I am building a first-order XO and adding time alignment for the 02 to address this very aspect of masking of the systems under test. Soon we’ll hear what happens when first order meets second order in the 02.
So, Jon, don’t be chagrined. Jim would have never accepted the coherence thing if he had not experienced it personally. Also, the coherence transperancy led to the need of inventing a better resistor and wire. I spent the summer of ’78 unraveling wire. Cousin Ted (our aerospace physicist) heard what we heard in the 03 prototype and suggested its similarities to low-level distortions in the Pioneer 10 / Jupiter probe communications, for which part of the solution was 6-9s (now CDA101) wire. I followed up his introduction to the project manager at ITT-NASA, and high purity, oxygen-free wire became standard in all our coils and wire from that point forward. That wire solution allowed final progress for the 03, in addition to radically changing how Jim admitted possibilities beyond his physicist / engineer comfort zone. I would call his perspective shift transformative, from quite skeptical to quite receptive. That cluster of events around first order and wire may be the defining elements of what made Thiel Thiel. Believing what we hear is crucial to real progress. Before landing on "For the Love of Music" as our first motto, another contender was "Believe It".

Tony - what model do you have?

1000 pair. Note these numbers are informal, compiled from Rob and highest observed serial numbers. They cross-check pretty well with other data streams and I update them with new information.

solobone - yes, there is a replacement. That "UltraTweeter" is used in the CS5, CS3.6 and CS2.2. Rob can tell you where to get (Madisound?) a direct replacement with a fiber dome rather than aluminum. Berger at Vifa designed both and likes them equally. Keep us posted as to what you learn.

sdl4 - The 2.2s are quite good, aren't they? And they're highly upgradable with better XO components and related goodies - when the time comes.

Regarding cable, I have rotated a dozen or so interconnects and speaker cables through my setup over the past couple years to reference my ears in my room and system. My favorite is Morrow. You might consider it, with their generous take-back trial deal.

jafant - I suppose my experience might have some instructive value. Note that my approach is not that of a hobbyist, but that of an experimental observer. My choices must approach the ideal, including the assumptions, general practice and choices of producers upstream. I recognize that is an impossible task, but within my constraints I try. For example, I chose Sennheiser 800S headphones, not only because they are very good, but because many high-end producers (mastering engineers, etc.) use them; so my potential personal preference for some other audiophile darling cans becomes functionally irrelevant. This is squishy territory which can cause a strict, skeptical engineer to abort - to conclude none of it matters, because it is a functionally unsolvable problem. I conclude that I must make my most balanced evaluations and choices toward this ephemeral ideal.
Let’s go to wire. I am lucky to have a personal beacon experience. Without an illuminating experience I can see being lost in the wilderness forever. You may remember cousin Ted, the aerospace physicist who suggested wire as a wild-card solution from GE’s deep space communications problems. I spent the summer of 1978 investigating, experimenting and choosing wire which became Thiel’s standard, and an early milestone for wire’s importance in audio. Over the years, Thiel compared various wire geometries, etc. and stayed with the 18-2 solid CDA101 in teflon for internal wiring. I am presently expanding that solution which we’ll address another time.
Interconnects and speaker cable are more complex, since we can’t predict the particulars of length, environment, and source and load characteristics, especially with speaker cable. Let’s stick to speaker cable. Before wire was a known thing in audio, Thiel started with homespun, getting pretty quickly to 00 welding cable, and around 1980 had our ears knocked off by Ray Kimber’s prototype braided wire at $1K/ pair foot. Someone here might remember the model name. I remember the radical improvement and that we beta tested further improvements of that flagship cable over the years. Astonishingly good both technically and to the ear. Jim developed a test bed to read various reactances in frequency, distortion and phase /time domains. I hear knowledgeable people claiming there are no meaningful measured differences - I say emphatically that is not true. I rather think that opening  Pandora’s Wire Box simply raises more questions and considerations than they want to address.

Back to cable. There was a stream of Kimber. Also there is Straightwire who was a close ally with Thiel from their beginning. Steven Hill is an engineer and has developed and explicated a significant knowledge base over the decades. At present I have some early Straightwire (model unknown) that I’ve lived with since the 1980s. One of my studio workhorses is Straightwire Octave II @ 4 runs in 12’ lengths, star quad with individual terminations that I can mix and match for mono and/or bi-wire or bi-amp. I am not in the listen and choose my favorite game myself, lacking the time, access or budget to do so, and eschewing my personal preference, while valuing "rightness" and "standardness" in my decision matrix. So my process goes like this: discuss with Steven what I want, weigh his solutions and technologies toward those goals and accept his recommendation as to where to land, which is generally the performance sweet spot of the brand. In this Case the Octave II is suitable for my purposes - I use it every day.

Let’s jump to preference. I prefer the Morrow SP-4, which I chose by a similar process, but in 12’ lengths it lacks some beef on the bottom. I have 4 runs which I can double and get the solidity I want. I could get it by running 6’ lengths (which I have demonstrated), but for my purposes, such non-standard runs defeats some of my reference purposes. Awhile back we explored here (or possibly behind the curtain with some of you, pardon my spotty memory) the pros and cons of parallel vs twisted runs. I agreed with those who preferred the parallel runs which produced an ephemeral, liquid-like presentation. But, my measurements and further listening led me to conclude that those pleasant effects were artifacts of delicious problematic behavior. Nix. So, I twist my double runs.
In addition to those brands, I have and use some old Audioquest, model unknown as well as Benchmark’s Canare, Bluejeans Belden, ProCo (professional) 12’ gauge star quad and OCOS (Dynaudio’s coax), as well as various Audioquest, MIT and who knows what that are occasionally borrowed for comparison. I use many of these wires in live recording and off-site playback duties, and can identify their sonic fingerprints. I know some folks here just don’t buy the wire thing, and you among others are committed to pursuing those nuances as a serious undertaking. I don’t claim to understand much of what goes on in wire, but do know that some serious stuff is going on. Part of the mix includes dielectric considerations and many manufacturers just don’t go there. Of the thermoplastics, the Teflon family wins, both in listening and measuring. The hierarchy is known and agreed, and, who would guess, more expensive performs better. As an anecdote, I quizzed John Siau of Benchmark about such dielectric considerations, to which he had no response, side-stepping to star-quad geometry’s cancellation of distortion mechanisms as the important factor. I bought his wire. It’s good, one up from ProCo, similar to Belden, but lacks the higher order performance of audiophile cable. I don’t think he could be convinced of such further considerations, but then that’s not my job.

I overlooked AntiCables. I like Paul’s approach and the product, and he seems now to be addressing directionality. I know that directionality matters, but I also know how wire is drawn and how little I could trust the process to yield consistent draw-down monitoring to guarantee which direction the crystals lie. Anyhow, directionality can be heard, so therefore probably tested via some method beyond my scope. In the ’no insulation is the best insulation’ stream, Morrow is on to a big deal. Grown cellulitic fibers are better dialectics than thermoplastics. Morrow uses cotton fiber, which is excellent. (Ever notice how great those paper capacitors can sound?)

I’ll mention a recent lesson from my internal wiring quest. Dialectic matters, and two or more different dialectics in the bundle is better than one - to spread out the anomalies. If we assume CDA101 (best) copper and great insulations, geometry is a really big deal. The cost and consistency of braiding are unfeasible to me. Small irregularities in braid more than undoes the advantages. Same-direction twist wins as an implementable solution well grounded in known physics and within reach of conscientious manufacturing processes. My proprietary configuration may end up being patented or proprietary to Straightwire, so I’ll not go further. And, believe it or not, craftsmanship is a far bigger issue than I assumed. Small physical / mechanical variations in my hand-laid samples create audible and measurable differences, which go way down with optimized mechanical lay-up.

I note that Jim ended up with Goertz flat wire and the Absolute Sound or Stereophile reviews of the 3.7 noted its superiority for that speaker. I have read about flat wire, but never heard any. And I wouldn’t go there myself because its market marginality would buck my practice of swimming mid-stream. So, that’s a look at my little corner of the world of wire. It’s a fascinating world, and one who’s dismissal would leave many delights unsavored. This post scratches the surface - there’s always more. I enjoy hearing your perspectives - I don’t get out much - and I should get back to work now.
Cheers

sdl - knowledge is lovely stuff, but never enough. At 72, some seeps in. I have used my 2.2s as my main playback tools for my whole professional life. I love them, but they will get better, similar to the improvements in beetlemania's 2.4 upgrade. Old Thiels age well and die hard.

I like Cardas, have evaluated some samples here, and like them a lot. But so much history with Straightwire precludes jumping that gunwale. Their focus on timing should matter a lot for Thiels. Tell us what you learn.
8M is a long way to run. I have that run for my 'far end' 3.6s to compare my nearfield 'corner launch' system under test to the mid-far field 3.6 reference. I'm getting best results with the OCOS (doubled) coax which is comparatively immune to cable run length. Have you tried an amp close behind each speaker with long interconnects? You could use Mogami, etc. pro interconnects as a trial. I could send you a pair for trials.

Carry on, there's always more to come.

snbeall - regarding cable theory - I am familiar with that Townshend paper and have kept up (as time and education allow) with cable development. Within the considerable snake oil in the cable corner of the market, I believe there is a lot of real, honest, verifiable truth. The stuff in the Townshend paper is consistent with my understanding of the arena.

As an anecdote, I collaborated briefly with John Dunlavy in the mid 1990s regarding cabinet design. I was amazed by John's grasp of and attention to wire considerations. John held multiple patents regarding antenna design, and thus paid close attention to electromagnetic and other propagation effects of signals through wires. His knowledge far surpassed my understanding, but his stack of patents and results in his speakers spoke volumes to me.
In general, I see parallel explorations between audio cable designers and high-level physics considerations, and much of the dismissal and ridicule coming from the engineering-oriented skeptics who want the designers to prove their points. As a manufacturing practitioner I know for certain that we plain can't afford the time, energy and approach of proving our improvements to anyone. We, as designer-manufacturers, have to do our innovating, get it to market and run as fast as we can to innovate again. Let the academic engineers fight it out, as long as our customers support our work.

snbeall- regarding the 02 / SCS / PP series. I do consider them true Thiels to the core. Yes, they use second order slopes because they were designed with home theater considerations, etc. But, Jim's implementation used both drivers positive polarity and a non-conventional alignment. That alignment plus the dispersion characteristics of the two drivers with large diameter differences, results in a flat room response and no excess energy at the crossover point. The 02 is quite unique in that regard. The fact that a box speaker can be placed on its side and/or at any height makes it susceptible to non-alignlment, which Jim's personality couldn't tolerate. So, the 02 directly led to the SCS with the coincident / concentric tweeter which yields a coherent wavefront, albeit with broader phase angle swings than first order, but never falling farther out-of-phase as do inverted polarity implementations.
Note that I use a pair of PowerPoint 1.2s as my room-filling / mixing references. That 45° launch was patented and is uniquely effective. My only suitable space in my studio is near the corners at the wall-ceiling joint, which works quite well - I have also demonstrated them on a floor, which works better. Ceiling was their design environment if you have a suitable situation. I built outboard crossovers for all ClarityCaps and Mills resistors. Better than stock.
I do have a quibble with the concentric driver in general. Through time Jim was able to create the double cone for a shallow, wave-guide geometry of the front cone with a deep, straight-back reinforcing back cone - minimizing the cupped hands effect, but it's still there a little. My enamourment with the 02 is to make a stand monitor with two discrete drivers, with Jim's second order style crossover and without the inherent problems of the concentric driver. Note that I do appreciate the concentric driver's ability to deliver coherent sound relatively independent of listener position. We can't always get it all. (Except perhaps with the radial wave 7 coaxes.

All - progress is being made toward the schematics and closure of the Thiel legalistics. I'll announce when I can.

Harry - good to see you. Thiel did have early exposure to Monster, I don't remember the models, but it was with their high-end offerings. I remember Audioquest bettering our Monsters and so on and so forth.
I don't know whether I mentioned our significant relationship with Monster. Jim had designed and patented a head amp circuit (his first patent) in the early days of moving coil cartridges where their very low outputs presented serious problems to the input circuitry of phone stages. Monster exclusively marketed that head amp and we swapped / beta-tested products with them until the late 1980s when cartridge outputs got higher, preamp circuits improved and CDs ran away with the market. I have a couple of those head amps if anyone wants to try one in a low-output moving coil system.

My redevelopment exploration over the past few years has identified this metallic source of interference. My experiments point to disruption of electromagnetic fields to create eddy currents that react against the orderly flow of energy.

In the 1978 development of the 03 (first coherent source) we discovered and substantiated such effects in steel driver baskets - independent of stiffness, ringing, etc. The electromagnetic eddy currents hang in time and cause subtle phase/time domain distortions. Solution: non-magnetic baskets. However, even non-magnetic conductors introduce electrical reactance when close enough to each other. Solution is non-conductive structures, both electric and magnetic. I don’t have test apparatus to prove such findings, but I understand them to be operative.

A new woofer I am working on will have a non-metallic basket. And my screws / bolts are reinforced nylon or Delrin. The improvement over brass/stainless steel is real, as is the improvement of brass /ss over conductive steel.

Such improvements are small, but additive - stack up several such small, subtle improvements, and the music sounds cleaner. I don’t know whether it matters that Dr. Toole might want more proof. I do know that we take extensive precautions against various bias traps.

You can play with hardware store supplies.

Robert - there are many details that are weighed in cost / benefit analyses relative to a company's market niche. Jim was the decider of what was worth what. I can't say for certain, but I suspect that those gold-plated bolts/screws on late Thiels are probably non-magnetic.

I had floated an idea (so of course I thought it had merit) to trick out a special line of each model with all these traded-off sonic upgrades and let the customers choose whether they were worth the cost.

Pete - it seems that Jim Thiel and Richard Vandersteen shared very similar approaches to their art. Jim's subwoofers also used the power amp output, and Jim's room correction was also done in the analog domain, for the reasons you stated.

I love what Richard did with his main amp bass rolloff to be re-boosted in the subwoofer - brilliant.

My wonderment includes that those two designers existed in such separate spaces: their products were never, that I know, compared; and their fans and users rarely overlapped. Interesting how markets and brand niches develop.

The cable thing is, in my opinion, a bigger deal with coherent speakers. I've spoken to the point previously, but to summarize I believe the ear-brain scrutinizes the music more critically when its coherence suggests real rather than reproduced music. When you get it all right, it's really right.

The SCS was the coax version of the 6.5" two-way that began with the 02 in 1976, the SCS in 1984 and on through the 2, 3 and 4.

One of the driving forces for the original SCS was our interplay with Toyota who built their Camry / Avalon plant up the road in Georgetown KY, beginning in the mid 1980s. Toyota's manufacturing model includes sourcing everything within a 50 mile radius of the assembly plant, which they modified to 100 miles for the larger distances in the USA. We waded into developing a luxury speaker system for the Lexus, and a coax was critical to that system since listeners are at various and changing distances and angles.

The project was intriguing, and Thiel eventually dropped out. The biggest contention was that they wanted Mark Levinson amplification, and Jim was unable to get ML to incorporate shaping circuitry into the amp designs. Japanese development engineering is extremely bureaucratic, authoritarian and invasive to internal company information, all of which didn't mesh with Jim's personal style. 
But, that first SCS coax came from that interaction which was further developed over the years for all the power-driver products.

I hope your dad enjoys them. 

Rob - take care when considering inductor gauge change. Although there may be no actual / functional differences, the fact remains that the coil resistance (as designed) is an integral part of the circuitry. Your change will change the circuit dynamics, and since Jim tuned those dynamics to a nub, I suspect you will not improve them. In fact, the differences may be small enough not to matter. But then consider what value are you getting? Note also that Thiel (ERSE - special) coil wire quality might be impossible to replicate in today's supply chain.

A real potential advantage is going from wire to foil, which acts more like a perfect inductor. In that case the Effective Series Resistance is quite different and may have even more impact on the circuit dynamics. In such case, you can re-establish the proper value / performance be inserting a series resistor after the coil, but its thermal dissipation will be considerably worse than the coil.

You might consider re-mounting the existing coil on stand-offs for more effective and even thermal dissipation than standard Thiel glue-down. That's where I have landed in my explorations. Just sharing a perspective.

Tom - I admire your deep-end solutions. I bet they sound good!

For my part, finding cost-effective upgrades that fit the general (albeit stretched) value proposition of Thiel Audio has landed me on Mills 12 watt audio resistors, quite good for $5.

I agree about removing the XO from the enclosure. Not only is there head-banging, there's gradually rising ambient temperature and proximity to driver magnetic fields. The CS2.4 got the XOs pretty far from the drivers, but better is better. I have two forms of exterior mounting. Full-blown is a separate cabinet about 2' behind the speaker that facilitates air-flow and allows more space between circuits. The first-tier upgrade puts the XO on the back of the cabinet. With vibrational isolation tech, we get pretty far along that road. We also get airflow and spread opportunities. I'm pleased with the improvements over stock - especially when the music gets dense, loud or long - the presentation stays much cleaner and more relaxed.

I get it. Too bad Thiel XOs are so complex. But that's what it takes to control a driver over 7 octaves without having detrimental effects on frequency, phase and time response.

One of these days I'll find the opportunity to put a Path in the critical tweeter feed.

TT

Tom - thanks for your comments. The entire arena fascinates me on multiple fronts. First is that "the problem" had been solved to our (Thiel's) satisfaction by 1983 with the CS3 contoured baffles that practically eliminated diffraction and baffle congestion. I didn't think a further problem existed.

My first hint was a demonstration that Doug Pauley did for a professional group (using a Tannoy speaker), that blew us away. We gathered further observational input from some leading audio industry luminaries, but the mechanics still remained mostly mysterious.

I pursued felt and flocking and Nextel, although I was unaware of Jon Dahlquist's explorations. Some of you beta-tested some of those solutions. They address the problem.

Then there was the CS3.6 thing that some of you reported where sometimes there was a screeching / pulsing / hashing, but no cause could be found. A couple months later I had narrowed down these so called 'sheer or propagation waves' on the baffle surface, primarily the flat area above the tweeter. 

The collaboration with Doug has applied his patented surface treatments for real advances toward mitigating a problem that had been unknown, unreported or otherwise invisible - but not inaudible.

BTW: you and I are on similar paths. I also ended up with genuine wool (F11) strategically placed on the walls. Also, there's a somewhat expensive addition via Ultrasuede - the real stuff - in the finest grade. US over F11 is where I was going before Doug came along and opened Pandora's Box. Thanks for the link and references.

JAFant - what I meant to say is that the stock CS2.4 has its crossovers positioned quite optimally - more so than most Thiel models. Here's some background.

Although we were aware of sonic degradation when the free-form / bird's nest development crossover was compacted onto a board and mounted in the cabinet, Jim's approach was to cause the least damage while incurring the least expense.  In many models there is very little room between all those shelf braces, and the XOs got even more compact(ed).

By the time of the CS2.4 development in 2002, the cabinets had much less bracing. Not being there, I could only speculate about rationales, which I won't. But there is plenty of room in there to mount two separate XOs away from each other and from the drivers. I believe that geometry aids the 2.4's clarity and openness.

To your previous question about Renaissance offerings. What has developed is going way back to the 1976 model 02 - bookshelf / stand-mount monitor, mainly for pragmatics. They're cheap, simple and easy to ship. Mine have morphed from second order to first order / coherent source topology, being used as workhorses to compare passive parts, xo layouts, drivers and new technologies. Of special note is Doug Pauley's twin patented technologies that tame wave-launch turbulence. Progress is being made.

At some time there will be a stand-alone short run of perhaps 50 pair of this re-imagined monitor. No promises or projections as to when.

 

The collective experience of many old-timers is that the room is far more important than is generally acknowledged and that effort spent there is worth some multiple of effort and expense for gear. Keep that in mind.

The CS2 is old, designed in 1984 and released in 1985. There are qualitatively better caps and resistors that can upgrade your sound. Your tweeter is obsolete; we are working on a replacement. Your midrange has a drop-in replacement / upgrade available through Coherent Source Service or directly from Madisound, the importing distributor. There is a long history on this thread of the flow and intent of an ongoing upgrade project.

I'll try to talk about the CS2 in particular soon - it hasn't yet been addressed.

 

Prof - it's hard to say. These various projects have taken on beta-partners, people who systematically build out the designs while carefully noting their listening experience as it goes. Eventually there may be all of what you list above, from advice to plans to kits to in-house upgrades to new Renaissance products. I know it's been a long time, but the project is still in early stages for reasons too quirky to itemize.

It is quite a trip, though.

Jim - Memory develops holes at 40 years out. This morning I pulled a tweeter on a CS3 I have in storage. Yep. The tweeter cavity has a 1/4" thick back with a lag bolt to the cabinet back. (No dodging - I did it!) That isolated the tweeter, plus was a quick-assembly method to clamp the baffle until the glue dried. And yes the bolt does add some structural stiffness for the tweeter mount.

But meanwhile, we learned about eddy-current distortions. On that front, that steel bolt is in line with the donut hole of the tweeter magnet which is the worst place for saturation distortion. I suggest that you'll get cleaner highs with the steel bolt gone. Best is no metal there at all (better than non-metallic which is better than what you have.)

That baffle is 2" thick. Deepening that pocket will remove the back, which is OK. The tweeter cup is sealed. I suggest adding some BluTac to the back of the tweeter cut to quiet any surface noise.

Tom D - the whole matter of bass is deep and sticky. I have spent considerable attention on the problem, and am still in the dark. But here are some thoughts. Put your boots on because we're going in over our heads.

At Thiel we did tons of (non-marketable) work on subs. There are so many issues  that we avoided the area until Home Theater required something. I think Jim's subwoofers deal with the issues extremely well. I have some now and agree with you that stereo subs are the way to go. There high enough frequencies for specifically directional cues. But of course its far more complicated than that.

Part of the problem is that there is no practical way (within budgets) to solve the bass phase issues which are so fundamental to Thiel designs above the deep bass. The (pre CS3.6) Model 3 family (plus the 01) had sealed enclosures which produce a perfectly damped low roll-off at 12dB/octave (second order) which mimics real acoustic instruments in real unrecorded spaces. Very satisfying bass. That bass roll-off introduces progressive phase shift that sounds natural because it is. Jim added active equalization to apply more amplifier power where needed in the bass without exceeding the power already required for clean midrange peaks.

However, when  a subwoofer (any subwoofer) is added there is an electronic crossover between the sub and the normal woofer, plus some unknown physical space offset injecting unknown time smear. Best case is a discontinuity that launches sub sound a full cycle behind woofer sound - albeit in-phase (I prefer "polarity") for augmentation. The ear-brain sorts out the temporal discontinuity, but not without consequences. What you do get is a pressurized environment (especially with stereo subs positioned closely) where the woofer "sees" a better physical impedance match between its force-motion and the air-space it is working into. Woofer distortion drops and articulation increases. 

Notice that on Jim's passive sub crossovers, you rarely actually hear the sub-bass. But it measures properly; it's there in the room. My fairly extensive auditioning and measurements corroborate his solution. Run the woofer full range for best placement and decay cues while using the sub just below audibility to create a better working environment for the woofer. The question arises as to how 'correct' the woofer signal is. In the retrospective work I am presently doing, and knowing intimately Jim's keen interest in 'the meaning of bass', I see Thiel's migration to reflex bass as a sell-out and know that it wasn't easy for him to accept. The transition from woofer to "port" (or passive radiator-same result) occurs at 4th order - 24dB/octave which puts the reflex fundamentals a full cycle behind the body of the bass coming from the woofer. Many folks (I'm one of them) hear that discontinuity as "slow bass" and less than natural, because it isn't. Reflex bass gets you an added octave (more of less) at extremely little cost, permitting overall system sensitivity to remain (twice) more efficient. Hard to side-step when nearly every peer does it even with speakers costing $6 figures.

Back to the question of how / why the laminar flow enhancements add so much sonic value - beyond understanding. Having spent the better part of the last couple years working on this problem I can offer some hints that may be gradually moving toward understandings. Let's examine some issues through the psycho-acoustic portal. We under-appreciate how much of what / how we hear is synthesized, including neural sub-circuits to enhance sonic recognition . . . we build models based on sonic inputs, not just from our ears, but also the mastoid process, and (lower than that) the solar plexus and skull and abdominal flexion and resonances. Saying that we don't hear below 20Hz is like saying we don't see outside some old-fashioned video frequency limits, or we don't smell unless we consciously identify what we're smelling. I know of weaponized sound at 3-6Hz, and euphoria-inducing sound at 7-12. Everything matters. Let's call it 'infrasonic' and pay attention.

Greg Lukens, the legendary inventor-audio engineer, evaluated an early version of DP's laminar flow technologies and hypothesized a sonic building-block explanation. The ear-brain builds its sonic conjectures (synthetic hearing) from the bass up. All harmonic structures are built on the foundation of the fundamentals. When those aren't there, the ear-brain "creates" them as phantom fundamentals. We don't know we're not hearing them. I posit that process of imagination to be quite benign. However, when we add that missing fundamental (as through a subwoofer) and that fundamental arrives at best a full cycle behind the upper harmonics and the upper harmonics of the subwoofer (or port, etc.) are a cycle behind the natural sonic structure coming from the woofer, we don't like it. We come to terms with it - we're quite excellent at accommodation - but nonetheless a lot of processing power is burned to get a less-than-satisfying hearing outcome.

We've gone pretty far here, mostly to address some of the difficulties of explaining a very complex subject. What I propose is that part of the reason we have such difficulty finding relevant measurements for the problems of "fake bass" or the bass-upper integration, or the unexplained imaging improvement, etc. is that these phenomena don't exist quite in the realm of the measurable. They exist in the realm of ideas and understanding, of epistemology - the study of how we know what we know, in this case what we hear. Let's posit (which I believe) that the surface-flow rectification contributes to fundamentally better organized leading-edge wavelaunch transients which produce substantially more lucid and interpretable fundamentals on which to build a harmonic stack that can be deconstructed into its component parts to sound like a musical event. Imagine that by removing significant chaos from those interacting onset transients, the auditory cortex can grasp the sonic event clearly whereas previously the event was dubious. A profoundly interesting aspect of my measurements is that "treated" laminar flow systems possess significantly better information from 0 to 20Hz than their untreated control system.  A very interesting aspect of all this is that we the listeners (controlled settings) do not necessarily attribute the sonic improvements to the bass, but more so call on qualitative observations such as "clarity, realness - accessible, involving, sweet, delicate, etc..  

So to your initial question regarding soundstage enhancement, I believe more brain power becomes available to deconstruct more spatial subtlety than when it was preoccupied with figuring out the basic harmonic structure of the sounds. Rather than technical measurements of the sound, we might come to greater understanding through brain activity monitoring.

That's all for now - For the Love of Music.

unsound - thank you as always for chiming in. Indeed a replacement driver is really the beginning of a redesign project and not the end. To elaborate: as you say, Jim considered all aspects as a system. Each driver has its Thiele/Small parameters carefully chosen for its tasks, plus its particular resonances and anomalies which he carefully modeled and corrected in the crossover such that the net acoustic roll-off was 6dB/octave with very flat impedance characteristics to realize very flat frequency, phase, time and impedance characteristics. Note that the only way he could get by with necessarily low impedances was by engineering an extremely resistive load. Changing a driver will change all or nearly all those parameters to defeat the subtleties of the design.

All that said, Madisound is a very knowledgeable distributor and they know a lot about their drivers. Rob has worked with them to choose the most appropriate available replacements.

Note also that Morel's inception was to pirate the Dynaudio designs, complete with international lawsuits, etc. So, the Morel replacements are quite likely the closest available replacement for the D28-AF.

Worth mentioning is the D28-AF was used in the CS2, CS3 and CS3.5. That 28mm driver has 20% more radiating area than 25mm domes.

As a generalization, I had hoped to endorse replacements by this time, but haven't gotten there yet. A real product update requires not only new drivers, but redesigned crossover networks. As a DIY, you can get pretty close with what's available, but a professional undertaking requires more diligence.

@sdecker - wow also. I didn't know about the wayback machine!

pieper1973 Nice work. Your CS2.4 serial numbers @253-4 are right near the transition from Lexington-made original boards with American / European parts, point to point on masonite boards - to FST-supplied clones. If your boards are printed circuits, they're from Asia, but your parts may be original, which I consider higher quality. What I know from Rob is that somewhere around 220-230, production went to Asia, and parts sourcing gradually migrated toward Asian parts.

Regarding your cap question. I've corroborated Jim's migration to single caps rather than the 1uF bypass. A single value is superior when the cap is of very high quality, which you are proposing. FYI: Jim tested all the high end caps and chose ClarityCap. I did also, landing on the ClarityCap CSA, which is considerably superior to the original SA. CSA has (or will soon have) an improved version called Purity or Purity+ with thicker copper end caps and even better performance than CSA, at lower prices than your targets. You might put them on your radar. Keep us posted.

About the CS2.4 serial numbers . . . I’ve been piecing together the history puzzle. What seems clear is that the transition to Asian inputs such as CS2.4 crossover manufacture was far from smooth or steady. Even though Rob says Lex 2.4 XO manufacture ceased around #220-230, that’s only part of the story. We have evidence from participants on this forum that later XOs were Lexington-built and that some later Asian XOs were decidedly inferior to some earlier ones. One key is that FST, the "best" supplier wasn’t the first supplier and that the road was pretty rocky to arriving at well-made units with top grade parts.

The Lexington XO department was not disabled until New Thiel moved to Nashville. While it was operational, runs of "old Thiel" crossovers could be and were made in Lexington with classic Thiel parts to fill in until acceptable units arrived from Asia.

With the records gone it seems the most reliable test is whether a board is built on masonite or not. If yes, then it is from Lexington with classic Thiel parts and QC - which means very tight performance assurance. If fiberglas, then more is unknown. Some Asian boards that I’ve seen are quite poor and some quite good.

Another potentially confusing element is the SE designation. The Signature Edition had a special cabinet with red Birdseye Maple veneer, SS bolts and outriggers, and larger, signed back plate. The only electronic upgrade was the ClarityCap SAs in the coax feed replacing the standard Solen caps. I think that run had its own serial numbers (1-300?) However many regular 2.4s have had the SE cap upgrade or better and some designated (red BE, etc.) SEs use Asian boards with SA caps. So, there are more variants of the 2.4 than might be assumed. I now have a pair on loan from a collaborator (#3729-30), in mature-Asian form with clean coils, polyester (MPT) caps and PP 1uF bypass caps, rather than classic polypropylene caps and tin-styrene bypasses. This is a de-spec iteration which I predict would sound inferior to a classic Thiel build. But it does sound delightful. Despite its somewhat shady history, what a wonderful product!

jafant - No retail space in the cards. Open studio space still a couple of dim possibilities. Workspace is materializing a little at a time.

The pictured XO looks just like mine. If 2951-2 look like that, they're from the same era. Those black caps are polyester-mylar (one down from polypropylene), the coils are well-made from CDA-102 wire, which is high-end regulation wire, one step down from Thiel CDA-101, which is the best available. I tested these resistors and found them to be the non-inductive resistors that Jim had designed and made by ERSE. Although they look like normal sand-cast, but are better. Note that these PCBs are actually point to point layouts with no traces that can cause troubles. This wire has Thiel signature teflon insulation. All in, I would be happy with these boards, unlike some we have seen with obviously poorly wound coils and unknown insulation.

That said, if you're DIY-inclined, you could elevate the sonics by upgrading all resistors to Mills MRA-12s and all film caps to CSAs with the 100uF electrolytics to some upgrade recommended on this forum. I have eliminated all electrolytics and have developed an affordable CSA-type 100uF cap that works well. Not ready yet. 

I don't want to open Pandora's Box regarding product iterations and quality levels. I'm told that all 2.4s were assembled in Lexington, approved by Jim and tested to the historical standards. I have expressed my personal disappointment that some particulars of parts quality eroded after my watch. But, compared to competitive products in design and execution, I suspect Thiel stayed way up on the value charts.

jazzman - you should be fine. It seems most of the "difficult period" might have been 2003-2004. Thiel probably found better sources, plus China definitely improved its development and manufacturing chops year on year. 

The the tell-tale test is looking at your boards for the winding quality of the coils.

A thought. It is asked whether phase/time really matters or if designers so inclined just pay close attention to everything, therefore producing successful products. This week's experiments might shed a little light.
You know Marena. We’ve been working together again in the times of waning Covid fears. She has great ears, a well developed musical sense, and is a performing singer-songwriter. We’re comparing Douglas Pauly’s turbulence control technologies which I call "laminar launch". We’re using the 02 because it’s easy, available and feasible to ship around the country for serial evaluation and input. I became irritated with the one cycle lead of the tweeter - distracting from the deep engagement needed to compare laminar launch variations. So I made 4 sample 02s. R: stock = Reference, which Doug has been using in California. A, B, and C, leap-frog upgrades till now all the same with Thiel CS.5 drivers and 02 XOs implemented with ERSE coils and their best caps plus Mills resistors on separate W and T boards, plus my new super-wire, and nicely braced cabinets with F11 felt on the baffles. Substantial performance improvement over stock. A, B and C all measure and sound very close to identical.

Enter the dark horse. I moved the woofer on A forward until the onset transient is time aligned. Still second order slopes, but all positive polarity and time-aligned, like an SCS / PowerPoint series. A's frequency response and harmonic distortion are undifferentiable from B and C. However, the impulse and step response now show time alignment. Excess phase and group delay are marginally improved. Of note is the waterfall plots behave better, which surprises me. The listening experience is qualitatively different. Subjectively, A now seems less forward, especially the high frequancy edge is gone. Gone. The differences read like many Thiel fans cite as their reasons for liking Thiel’s sound.

Marena and I have practically written each others' comments regarding the improvements.

But now I have a treat to add from this morning. My home is a small village of 1000. I have known Lincoln Fedicovich since he was born, as a rambunctious child and now a hard-working young man of 20, who is helping me move my shop/studio on short notice - another story. When he came for work this morning I asked if he would help me listen. His reply was "sure, but I’m not very musical". My test cut was Sarah Jaroz "Peace" from her "Follow Me Down" album. As is our custom, Lincoln listens blind, in his case very blind with no musical or hi-fi experience, knowing only speaker A and B, each fed a mono-mixed signal through the Classe DR6 to bridged dedicated AHB-2s for each channel. A & B are 4’ apart with listening line 6’ out. Play A, Play B, chat: Lincoln is my ideal "naive listener", interested but quite unexposed or opinionated. He said: "A was more crisp, clearer in every way. B was more like a speaker. Then I told him they were identical speakers except that A’s woofer was on a stand-off to make the music from both drivers arrive at the same time. I added that many experts think that doesn’t matter. We repeated A & B after which he said: "B still seems like a speaker. A is more like the music is here, happening in front of me. Can we listen in stereo?" We did after which he added: A is overwhelming better if every way, like it’s real".

Then he added. "I always wanted to learn guitar. My grandma played lots of music for me growing up. Everything: Classical, Bach, Beethoven, Mozart, country folk, Johnny Cash, Nelson - lots of stuff. I haven't thought of that in years. This is good stuff."

He agreed to help listen whenever I want. Now, how’s that for Saturday morning before getting to work on moving!

improvedsound- you’re in the deep end, so take care.

My knowledge is anecdotal and experiential. I have experimented with foil inductors enough to learn that I’m over my head. Indeed a foil inductor is a more perfect inductor than any wire inductor. However all components exhibit all characteristics ie, an inductor also has resistance and capacitance plus the products of reflectance interactions between them - and time factors as these interactions play out. So, changing anything changes everything. Flash back to my direct observation of Jim’s learning curve about these matters, as each iteration of each product grew into its maturity. Part of that advancement is about understanding and implementing more aspects of such component interactions.

There are direct aspects that can be adjusted. A foil coil will have much less series resistance and different capacitance characteristics in space and time per equal inductance value. In some cases those changes can be corrected via addition of a series resistor and/or layout changes to compensate for circuit capacitance and resonance variables. I have been able to accomplish some of these requirements in my experimentation and coaching. However, I’ll say it again, I’m a novice and not qualified to re-engineer Jim’s work beyond basic changes.

So I keep the extant inductors because I know them to be best-of-form (at any price), providing an anchor for any other circuit changes. Similarly with caps, ClarityCap provides very predictable performance in all measured aspects - it’s no accident that they are an industrial / aerospace / professional company making products based on solid engineering performance. (I have tested and measured some brands that de-spec some aspects to achieve some euphonic outcome.) A person could spend a lifetime making sense of the correlations. I’m keeping it simple enough for me to make sense of it within my constraints.

Regarding resistors - the Mills sound better than Jim’s. Fair enough, they cost 5x as much. Jim developed, from first principles, what is called the Ayrton-Perry winding which is non-inductive with minimal parallel capacitance within an inexpensive sand-cast case. His circuits and layout assume those A-P characteristics. I know that Mills MRA-12 is a direct drop-in with the same characteristics. However, I don’t know much for certain about Path, or film or bridges. I do know that altering the type of resistor or any component will have effects that are sonically important. I also know the hundreds, perhaps thousands of hours learning by listening and integrating with fundamentals of physics to get the holistic design expressed in each product as designed.

I do not have the knowledge to help unravel what might be going on when some component is changed. I do know enough to be extremely cautious and make changes that don’t screw anything up. I do not deny that some folks have gotten results they are quite happy with, but the system is complex enough that a dose of luck could be operative. So for myself, caution wins. Trust your ears. If something sounds "off", call it off. Then the fun begins putting Humpty-Dumpty together again.

This very long answer is to recap territory we’ve explored in these 223 pages over that past few years, which new participants probably haven’t read. Keep the faith, learning is good.

At TA I always cultivated “Lincolns” and their contribution was invaluable.
others here might supply more technical explanation of XO slopes; Here’s my layman’s take, IF a system creates a proper step response, it is phase/time coherent. Jim’s second order XOs in the 02/SCS series do create such steps, because he kept polarity positive and he used beaming of the largish woofer to good effect. It works whereas most 2nd order executions don’t. Nevertheless, there are more reactance and wider phase and impedance swings in the second order. First order is more ideal BUT 1st order requires much more sophisticated drivers. I am presently comparing 1st vs 2nd in the O2, which is of great interest to me. I’ll report findings. Marena and Lincoln will keep me honest.

A variant of the Lincoln Effect, which I have come to use extensively, is the Background Effect. Playing music in the background, while I work, in and out of the room and while assessing technical measurements, has an interesting effect. I play the next CD up, and I play it all day, and I take mental notes of tracks with particular effects or utility. My comment is on the different kind of evaluation of the speaker under test which is occurring in that mode. There is a global assessment of appeal or resistance, of feeling-states or level and kind of involvement, which, over time, associates with speaker component evaluation and selection. It seems unlikely that those observations would come to the surface via directed, focused, evaluative listening sessions. As sdecker says, we're too focused on the minutiae and technical to allow the global to penetrate.
This effect is similar to what many pros have mentioned. A new set of headphones or preamp, or mixer, etc. takes about two weeks to 'settle in'. They don't typically talk about equipment burn-in, but rather a form of psychological familiarity or knowing that allows a final accept/reject decision - to use or not to use for their technical art. I know that people on this thread have expressed this factor as their interpretation of what 'burn-in' is really about. There is truth there, along with truth of component maturation under stress.

Anyhow, this week I hope to compare first vs second order, both time-aligned in the 02.  (while packing and preparing to move - what a trip.)